google/gale/Kconfig: Change wording of Kconfig option

Everybody knows WHAT they're supposed to do with options, so the text
"Pick this" or "Select to" are redundant.

Change-Id: I327c5be755373e99ca0738593bd78e1084d4d492
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/16838
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/mainboard/google/gale/Kconfig

@@ -37,7 +37,7 @@ config CHROMEOS
 	select WIPEOUT_SUPPORTED
 
 config BOARD_VARIANT_DK01
-	bool "pick this to build an image for DK01"
+	bool "Build an image for DK01"
 	default n
 
 config MAINBOARD_DIR