regulator: core kbuild files

This patch adds kernel build support for the regulator core.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 257033c..4b8acd2 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1225,6 +1225,8 @@
 
 source "drivers/dca/Kconfig"
 
+source "drivers/regulator/Kconfig"
+
 source "drivers/uio/Kconfig"
 
 endmenu