ARM: mach-shmobile: mackerel: enable REGULATOR in defconfig

As well as being a generally sane thing to do this
is required for MMCIF to function in conjunction with
" ARM: shmobile: streamline mackerel SD and MMC devices".

Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/arch/arm/configs/mackerel_defconfig b/arch/arm/configs/mackerel_defconfig
index ec8e605..9fb1189 100644
--- a/arch/arm/configs/mackerel_defconfig
+++ b/arch/arm/configs/mackerel_defconfig
@@ -75,6 +75,7 @@
 CONFIG_I2C_SH_MOBILE=y
 # CONFIG_HWMON is not set
 # CONFIG_MFD_SUPPORT is not set
+CONFIG_REGULATOR=y
 CONFIG_FB=y
 CONFIG_FB_MODE_HELPERS=y
 CONFIG_FB_SH_MOBILE_LCDC=y