regmap: Add I2C bus support

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index fc0eb1d4..03cf1ab 100644
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -3,4 +3,8 @@
 # subsystems should select the appropriate symbols.
 
 config REGMAP
+	default y if REGMAP_I2C
 	bool
+
+config REGMAP_I2C
+	tristate