microblaze: Move MSR instruction selection to Kconfig

Select MSR instructions via Kconfig instead of xparameters.h.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/microblaze/include/asm/asm.h

@@ -50,7 +50,7 @@
 #define NOP	__asm__ __volatile__ ("nop");
 
 /* use machine status registe USE_MSR_REG */
-#if XILINX_USE_MSR_INSTR == 1
+#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR == 1
 #define MSRSET(val) \
 	__asm__ __volatile__ ("msrset r0," #val );