[MIPS] Rewrite spurious_interrupt from assembler to C.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/dec/int-handler.S b/arch/mips/dec/int-handler.S
index 41fa372..5bafd58 100644
--- a/arch/mips/dec/int-handler.S
+++ b/arch/mips/dec/int-handler.S
@@ -282,7 +282,9 @@
 #endif
 
 spurious:
-		j	spurious_interrupt
+		jal	spurious_interrupt
+		 nop
+		j	ret_from_irq
 		 nop
 		END(decstation_handle_int)