soc/intel/broadwell/pch: Rename GPIO identifiers

Rename structs, types and functions to match Lynx Point's names.

Tested with BUILD_TIMELESS=1, Purism Librem 13 v1 remains identical.

Change-Id: I11ea27b00b5820eb5553712e0420836470ec0d27
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50064
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/intel/wtm2/gpio.c

@@ -2,7 +2,7 @@
 
 #include <soc/gpio.h>
 
-const struct gpio_config mainboard_gpio_config[] = {
+const struct pch_lp_gpio_map mainboard_gpio_map[] = {
 	PCH_GPIO_NATIVE,        /* 0: LPSS_UART1_RXD */
 	PCH_GPIO_NATIVE,        /* 1: LPSS_UART1_TXD */
 	PCH_GPIO_NATIVE,        /* 2: LPSS_UART1_RTS_N_R */