MIPS: Cavium: Add -Werror

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/cavium-octeon/Makefile b/arch/mips/cavium-octeon/Makefile
index 1c2a7fa..d6903c3 100644
--- a/arch/mips/cavium-octeon/Makefile
+++ b/arch/mips/cavium-octeon/Makefile
@@ -14,3 +14,5 @@
 obj-y += octeon-memcpy.o
 
 obj-$(CONFIG_SMP)                     += smp.o
+
+EXTRA_CFLAGS += -Werror