staging: fbtft: Allow compile test of GPIO consumers if !GPIOLIB

The GPIO subsystem provides dummy GPIO consumer functions if GPIOLIB is
not enabled. Hence drivers that depend on GPIOLIB, but use GPIO consumer
functionality only, can still be compiled if GPIOLIB is not enabled.

Relax the dependency on GPIOLIB if COMPILE_TEST is enabled, where
appropriate.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Acked-by: Linus Walleij <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/fbtft/Kconfig

···
 menuconfig FB_TFT
 	tristate "Support for small TFT LCD display modules"
-	depends on FB && SPI && GPIOLIB
+	depends on FB && SPI
+	depends on GPIOLIB || COMPILE_TEST
 	select FB_SYS_FILLRECT
 	select FB_SYS_COPYAREA
 	select FB_SYS_IMAGEBLIT