mb/google/fatcat: Move battery LED logic to platform hook

This patch moves the ChromeEC battery-low LED signaling from the
Panther Lake SoC romstage code to the Fatcat mainboard-specific
romstage.

By utilizing the platform_romstage_pre_mem() hook, we remove Google-
specific EC logic from the generic Intel SoC directory, adhering better
to the separation of concerns between SoC and Mainboard code.

- Implement platform_romstage_pre_mem() in google/fatcat.
- Remove redundant EC include and LED logic from Panther Lake SoC.

Change-Id: I09f7dd516f1a98cf99313db379cfbef5157c9869
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/91000
Reviewed-by: Jérémy Compostella <jeremy.compostella@intel.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Pranava Y N <pranavayn@google.com>

src/mainboard/google/fatcat/romstage.c

@@ -1,6 +1,8 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 
+#include <arch/romstage.h>
 #include <baseboard/variants.h>
+#include <ec/google/chromeec/ec.h>
 #include <fsp/api.h>
 #include <soc/romstage.h>
 #include <soc/soc_chip.h>
@@ -43,3 +45,10 @@ void mainboard_memory_init_params(FSPM_UPD *memupd)
 	/* Override FSP-M UPD per board if required. */
 	variant_update_soc_memory_init_params(memupd);
 }
+
+void platform_romstage_pre_mem(void)
+{
+	/* Set LED to Red to alert the user visually */
+	if (CONFIG(EC_GOOGLE_CHROMEEC) && google_chromeec_is_critically_low_on_battery())
+		google_chromeec_set_lightbar_rgb(0xff, 0xff, 0x00, 0x00);
+}