mb/google/rex: Rename GPP_D07 to FPMCU_UWB_MUX_SEL

BUG=b:263412235
TEST=Able to build and boot Google/Rex.

Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: Ia444cc8e3666fe15479ece81d068f9e8f1d339ea
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71228
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ivy Jian <ivy.jian@quanta.corp-partner.google.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
diff --git a/src/mainboard/google/rex/variants/rex0/gpio.c b/src/mainboard/google/rex/variants/rex0/gpio.c
index a0869af..128fd32 100644
--- a/src/mainboard/google/rex/variants/rex0/gpio.c
+++ b/src/mainboard/google/rex/variants/rex0/gpio.c
@@ -168,8 +168,8 @@
 	PAD_NC(GPP_D05, NONE),
 	/* GPP_D06 : net NC.  Test pad.*/
 	PAD_NC(GPP_D06, NONE),
-	/* GPP_D07 : net NC.  Test pad. */
-	PAD_NC(GPP_D07, NONE),
+	/* GPP_D07 : [] ==> FPMCU_UWB_MUX_SEL */
+	PAD_CFG_GPO_LOCK(GPP_D07, 1, LOCK_CONFIG),
 	/* GPP_D08 : net NC.  Test pad. */
 	PAD_NC(GPP_D08, NONE),
 	/* GPP_D09 : [] ==> I2S_MCLK_R */