ARM: shmobile: defconfig: Update shmobile_defconfig

Update the defconfig for Renesas ARM systems:
  - Compile the kernel with warnings as errors.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm/configs/shmobile_defconfig

diff --git a/arch/arm/configs/shmobile_defconfig b/arch/arm/configs/shmobile_defconfig
index 8c30ed1..0030225 100644
--- a/arch/arm/configs/shmobile_defconfig
+++ b/arch/arm/configs/shmobile_defconfig
@@ -1,3 +1,4 @@
+CONFIG_WERROR=y
 CONFIG_SYSVIPC=y
 CONFIG_NO_HZ_IDLE=y
 CONFIG_IKCONFIG=y