Kernel: Use operator ""sv in all purpose() implementations

Previously there was a mix of returning plain strings and returning
explicit string views using `operator ""sv`. This change switches them
all to standardized on `operator ""sv` as it avoids a call to strlen.

Kernel/Bus/USB/UHCI/UHCIController.h

@@ -36,7 +36,7 @@ public:
     static KResultOr<NonnullRefPtr<UHCIController>> try_to_initialize(PCI::DeviceIdentifier const& pci_device_identifier);
     virtual ~UHCIController() override;
 
-    virtual StringView purpose() const override { return "UHCI"; }
+    virtual StringView purpose() const override { return "UHCI"sv; }
 
     virtual KResult initialize() override;
     virtual KResult reset() override;

Kernel/Firmware/ACPI/Parser.h

@@ -48,7 +48,7 @@ public:
 
     static void must_initialize(PhysicalAddress rsdp, PhysicalAddress fadt, u8 irq_number);
 
-    virtual StringView purpose() const override { return "ACPI Parser"; }
+    virtual StringView purpose() const override { return "ACPI Parser"sv; }
     virtual bool handle_irq(const RegisterState&) override;
 
     Optional<PhysicalAddress> find_table(const StringView& signature);

Kernel/Interrupts/APIC.cpp

@@ -79,7 +79,7 @@ public:
     virtual bool eoi() override;
 
     virtual HandlerType type() const override { return HandlerType::IRQHandler; }
-    virtual StringView purpose() const override { return "IPI Handler"; }
+    virtual StringView purpose() const override { return "IPI Handler"sv; }
     virtual StringView controller() const override { return nullptr; }
 
     virtual size_t sharing_devices_count() const override { return 0; }
@@ -110,7 +110,7 @@ public:
     virtual bool eoi() override;
 
     virtual HandlerType type() const override { return HandlerType::IRQHandler; }
-    virtual StringView purpose() const override { return "SMP Error Handler"; }
+    virtual StringView purpose() const override { return "SMP Error Handler"sv; }
     virtual StringView controller() const override { return nullptr; }
 
     virtual size_t sharing_devices_count() const override { return 0; }

Kernel/Interrupts/IRQHandler.h

@@ -27,7 +27,7 @@ public:
     virtual bool eoi() override;
 
     virtual HandlerType type() const override { return HandlerType::IRQHandler; }
-    virtual StringView purpose() const override { return "IRQ Handler"; }
+    virtual StringView purpose() const override { return "IRQ Handler"sv; }
     virtual StringView controller() const override { return m_responsible_irq_controller->model(); }
 
     virtual size_t sharing_devices_count() const override { return 0; }

Kernel/Interrupts/SharedIRQHandler.h

@@ -32,7 +32,7 @@ public:
     virtual bool is_sharing_with_others() const override { return false; }
 
     virtual HandlerType type() const override { return HandlerType::SharedIRQHandler; }
-    virtual StringView purpose() const override { return "Shared IRQ Handler"; }
+    virtual StringView purpose() const override { return "Shared IRQ Handler"sv; }
     virtual StringView controller() const override { return m_responsible_irq_controller->model(); }
 
 private:

Kernel/Interrupts/SpuriousInterruptHandler.cpp

@@ -41,7 +41,7 @@ bool SpuriousInterruptHandler::eoi()
 StringView SpuriousInterruptHandler::purpose() const
 {
     if (!m_real_handler)
-        return "Spurious Interrupt Handler";
+        return "Spurious Interrupt Handler"sv;
     return m_real_handler->purpose();
 }
 

Kernel/Interrupts/UnhandledInterruptHandler.h

@@ -21,7 +21,7 @@ public:
     [[noreturn]] virtual bool eoi() override;
 
     virtual HandlerType type() const override { return HandlerType::UnhandledInterruptHandler; }
-    virtual StringView purpose() const override { return "Unhandled Interrupt Handler"; }
+    virtual StringView purpose() const override { return "Unhandled Interrupt Handler"sv; }
     virtual StringView controller() const override { VERIFY_NOT_REACHED(); }
 
     virtual size_t sharing_devices_count() const override { return 0; }

Kernel/Storage/AHCIPortHandler.h

@@ -36,7 +36,7 @@ public:
     virtual ~AHCIPortHandler() override;
 
     RefPtr<StorageDevice> device_at_port(size_t port_index) const;
-    virtual StringView purpose() const override { return "SATA Port Handler"; }
+    virtual StringView purpose() const override { return "SATA Port Handler"sv; }
 
     AHCI::HBADefinedCapabilities hba_capabilities() const;
     NonnullRefPtr<AHCIController> hba_controller() const { return m_parent_controller; }

Kernel/Storage/IDEChannel.h

@@ -99,7 +99,7 @@ public:
     RefPtr<StorageDevice> master_device() const;
     RefPtr<StorageDevice> slave_device() const;
 
-    virtual StringView purpose() const override { return "PATA Channel"; }
+    virtual StringView purpose() const override { return "PATA Channel"sv; }
 
     virtual bool is_dma_enabled() const { return false; }
 

Kernel/Time/HardwareTimer.h

@@ -70,7 +70,7 @@ public:
     virtual StringView purpose() const override
     {
         if (TimeManagement::the().is_system_timer(*this))
-            return "System Timer";
+            return "System Timer"sv;
         return model();
     }