[MIPS] SEAD defconfig build fix

Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index d333ce4..f4227d2 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -330,6 +330,7 @@
 # MIPS SEAD board
 #
 core-$(CONFIG_MIPS_SEAD)	+= arch/mips/mips-boards/sead/
+cflags-$(CONFIG_MIPS_SEAD)	+= -Iinclude/asm-mips/mach-mips
 load-$(CONFIG_MIPS_SEAD)	+= 0xffffffff80100000
 
 #