mfd: twl-core: Fix incorrect function name twl_regcache_bypass()

Fixes the following W=1 kernel build warning(s):

 drivers/mfd/twl-core.c:496: warning: expecting prototype for twl_regcache_bypass(). Prototype was for twl_set_regcache_bypass() instead

Cc: Tony Lindgren <tony@atomide.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Kai Svahn <kai.svahn@nokia.com>
Cc: syed khasim <x0khasim@ti.com>
Cc: linux-omap@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/twl-core.c

@@ -485,7 +485,7 @@ int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
 EXPORT_SYMBOL(twl_i2c_read);
 
 /**
- * twl_regcache_bypass - Configure the regcache bypass for the regmap associated
+ * twl_set_regcache_bypass - Configure the regcache bypass for the regmap associated
  *			 with the module
  * @mod_no: module number
  * @enable: Regcache bypass state