use bool here, to avoid missing symbol on i2s module load

target/linux/patches/3.12.33/regmap-bool.patch

@@ -0,0 +1,20 @@
+diff -Nur linux-3.12.33.orig/drivers/base/regmap/Kconfig linux-3.12.33/drivers/base/regmap/Kconfig
+--- linux-3.12.33.orig/drivers/base/regmap/Kconfig	2014-11-15 13:28:07.000000000 +0100
++++ linux-3.12.33/drivers/base/regmap/Kconfig	2014-12-04 11:18:59.146540398 +0100
+@@ -10,13 +10,13 @@
+ 	bool
+ 
+ config REGMAP_I2C
+-	tristate
++	bool
+ 
+ config REGMAP_SPI
+-	tristate
++	bool
+ 
+ config REGMAP_MMIO
+-	tristate
++	bool
+ 
+ config REGMAP_IRQ
+ 	bool