microblaze: Fix IRQ flag handling for MSR=0

Patch: Fix IRQ flag handling naming
(sha1: f9ee29270c11dba7d0fe0b83ce47a4d8e8d2101)
introduced problem on system with MSR=0.
Signed-off-by: Michal Simek <monstr@monstr.eu>

arch/microblaze/include/asm/irqflags.h

@@ -12,7 +12,7 @@
 #include <linux/types.h>
 #include <asm/registers.h>
 
-#ifdef CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
+#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
 
 static inline unsigned long arch_local_irq_save(void)
 {