rfkill: Regulator consumer driver for rfkill

Add a regulator consumer driver for rfkill to enable controlling radio
transmitters connected to voltage regulators using the regulator
framework.

A new "vrfkill" virtual supply is provided to use in platform code.

Signed-off-by: Guiming Zhuo <gmzhuo@gmail.com>
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/rfkill/Makefile b/net/rfkill/Makefile
index 6621053..d9a5a58 100644
--- a/net/rfkill/Makefile
+++ b/net/rfkill/Makefile
@@ -5,3 +5,4 @@
 rfkill-y			+= core.o
 rfkill-$(CONFIG_RFKILL_INPUT)	+= input.o
 obj-$(CONFIG_RFKILL)		+= rfkill.o
+obj-$(CONFIG_RFKILL_REGULATOR)	+= rfkill-regulator.o