Fix Kconfig dependency for WM97xx battery driver

It needs the WM97xx touchscreen driver to be compiled in, not as a
module.  And it cannot itself be a module, due to some unfortunate
interactions with platform data.
Reported-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/power/Kconfig

@@ -58,7 +58,7 @@ config BATTERY_TOSA
 
 config BATTERY_WM97XX
 	bool "WM97xx generic battery driver"
-	depends on TOUCHSCREEN_WM97XX
+	depends on TOUCHSCREEN_WM97XX=y
 	help
 	  Say Y to enable support for battery measured by WM97xx aux port.