i2c: I2C bus multiplexer driver pca954x

I2C driver for PCA954x I2C multiplexer series.

Signed-off-by: Michael Lawnick <ml.lawnick@gmx.de>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index efb48ad..30f06e9 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -58,6 +58,8 @@
 	  This support is also available as a module.  If so, the module
 	  will be called i2c-mux.
 
+source drivers/i2c/muxes/Kconfig
+
 config I2C_HELPER_AUTO
 	bool "Autoselect pertinent helper modules"
 	default y