mediatek: 6.18: add missing module dependency

Add missing dependency of kmod-btmtkuart on kmod-hci-uart when building
with Linux 6.18.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

Author: dangowrt

target/linux/mediatek/modules.mk

@@ -18,7 +18,8 @@ $(eval $(call KernelPackage,ata-ahci-mtk))
 define KernelPackage/btmtkuart
   SUBMENU:=Other modules
   TITLE:=MediaTek HCI UART driver
-  DEPENDS:=@TARGET_mediatek_mt7622 +kmod-bluetooth +kmod-btmtk +mt7622bt-firmware
+  DEPENDS:=@TARGET_mediatek_mt7622 +kmod-bluetooth +kmod-btmtk +mt7622bt-firmware \
+	   +!LINUX_6_12:kmod-hci-uart
   KCONFIG:=CONFIG_BT_MTKUART
   FILES:= \
 	$(LINUX_DIR)/drivers/bluetooth/btmtkuart.ko