mb/google/kukui: Add a new config 'Fennel'

A new board introduced to Kukui family.

BUG=b:162478693
TEST=make # select Fennel
BRANCH=kukui

Signed-off-by: xiatao5 <xiatao5@huaqin.corp-partner.google.com>
Change-Id: I1f742a36793f38c37fbd4e1b4cbddbd542e785ec
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44061
Reviewed-by: Zhuohao Lee <zhuohao@google.com>
Reviewed-by: Zhuohao Lee <zhuohao@chromium.org>
Reviewed-by: Zhaoyou Hong <hongzhaoyou@huaqin.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/kukui/Kconfig

@@ -57,6 +57,7 @@ config MAINBOARD_PART_NUMBER
 	default "Willow" if BOARD_GOOGLE_WILLOW
 	default "Esche" if BOARD_GOOGLE_ESCHE
 	default "Burnet" if BOARD_GOOGLE_BURNET
+	default "Fennel" if BOARD_GOOGLE_FENNEL
 
 config DRIVER_TPM_SPI_BUS
 	hex

src/mainboard/google/kukui/Kconfig.name

@@ -57,3 +57,7 @@ config BOARD_GOOGLE_ESCHE
 config BOARD_GOOGLE_BURNET
 	bool "->  Burnet"
 	select BOARD_GOOGLE_JACUZZI_COMMON
+
+config BOARD_GOOGLE_FENNEL
+	bool "->  Fennel"
+	select BOARD_GOOGLE_JACUZZI_COMMON