mb/google/kukui: Drop non-existent directory from subdir-y

Change-Id: Ifafec925439375dc2c9237244eff24c7bbe56bd6
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/86486
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yidi Lin <yidilin@google.com>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>

src/mainboard/google/kukui/Makefile.mk

@@ -1,7 +1,6 @@
 ## SPDX-License-Identifier: GPL-2.0-only
 
 subdirs-y += sdram_params/
-subdirs-y += panel_params/
 
 bootblock-y += bootblock.c
 bootblock-y += reset.c