drivers/smmstore: Clarify Kconfig cbfs wording

Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Change-Id: Ibb37c2d99c1a95b1d37bec784c98e636da4836d9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38470
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/smmstore/Kconfig

@@ -21,7 +21,7 @@ config SMMSTORE_IN_CBFS
 	bool
 	default n
 	help
-	  Select this if you want to the SMMSTORE region in a
+	  Select this if you want to add an SMMSTORE region to a
 	  cbfsfile in a cbfs FMAP region
 
 if SMMSTORE