clk: tegra: divider: Mark Memory Controller clock as read-only

The Memory Controller (MC) clock rate can't be simply changed and nothing
in kernel need to change the rate, hence let's make the clock read-only.
This id also needed for the EMC driver because timing configuration may
require the MC clock diver to be disabled, that is handled by the EMC
clock / EMC driver integration and CLK framework shall not touch the
MC divider configuration on the EMC clock rate change.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/tegra/clk-divider.c

@@ -175,6 +175,7 @@ struct clk *tegra_clk_register_mc(const char *name, const char *parent_name,
 				  void __iomem *reg, spinlock_t *lock)
 {
 	return clk_register_divider_table(NULL, name, parent_name,
-					  CLK_IS_CRITICAL, reg, 16, 1, 0,
+					  CLK_IS_CRITICAL,
+					  reg, 16, 1, CLK_DIVIDER_READ_ONLY,
 					  mc_div_table, lock);
 }