MIPS: microMIPS: Add support for exception handling.

All exceptions must be taken in microMIPS mode, never in classic
MIPS mode or the kernel falls apart. A few NOP instructions are
used to maintain the correct alignment of microMIPS versions of
the exception vectors.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
diff --git a/arch/mips/kernel/smtc-asm.S b/arch/mips/kernel/smtc-asm.S
index 76016ac..2866863 100644
--- a/arch/mips/kernel/smtc-asm.S
+++ b/arch/mips/kernel/smtc-asm.S
@@ -49,6 +49,9 @@
 	.text
 	.align 5
 FEXPORT(__smtc_ipi_vector)
+#ifdef CONFIG_CPU_MICROMIPS
+	nop
+#endif
 	.set	noat
 	/* Disable thread scheduling to make Status update atomic */
 	DMT	27					# dmt	k1