target-microblaze: Tighten up TCGv_i32 vs TCGv type usage

Tighten up TCGv_i32 vs TCGv type usage. Avoid using TCGv when
TCGv_i32 should be used.

This is in preparation for adding 64bit addressing support.
No functional change.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>

target/microblaze/helper.c

@@ -69,7 +69,7 @@ int mb_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
 
     /* Translate if the MMU is available and enabled.  */
     if (mmu_available && (env->sregs[SR_MSR] & MSR_VM)) {
-        target_ulong vaddr, paddr;
+        uint32_t vaddr, paddr;
         struct microblaze_mmu_lookup lu;
 
         hit = mmu_translate(&env->mmu, &lu, address, rw, mmu_idx);