mediatek: enable bootargs-override for filogic subtarget

The ASUS TUF-AX4200 bootloader adds invalid parameters for the rootfs.
Without overwriting the cmdline, the kernel crashes when trying to
attach the rootfs, as OpenWrt uses a different partition than the vendor
OS.

Signed-off-by: David Bauer <mail@david-bauer.net>

target/linux/mediatek/filogic/config-5.15

@@ -50,6 +50,7 @@ CONFIG_BSD_PROCESS_ACCT_V3=y
 CONFIG_CC_HAVE_STACKPROTECTOR_SYSREG=y
 CONFIG_CLKSRC_MMIO=y
 CONFIG_CLONE_BACKWARDS=y
+CONFIG_CMDLINE_OVERRIDE=y
 CONFIG_COMMON_CLK=y
 CONFIG_COMMON_CLK_MEDIATEK=y
 # CONFIG_COMMON_CLK_MT2712 is not set

target/linux/mediatek/patches-5.15/901-arm-add-cmdline-override.patch

@@ -35,3 +35,20 @@
  	/*
  	 * CONFIG_CMDLINE is meant to be a default in case nothing else
  	 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
+--- a/arch/arm64/Kconfig
++++ b/arch/arm64/Kconfig
+@@ -1942,6 +1942,14 @@ config CMDLINE_FORCE
+ 
+ endchoice
+ 
++config CMDLINE_OVERRIDE
++	bool "Use alternative cmdline from device tree"
++	help
++	  Some bootloaders may have uneditable bootargs. While CMDLINE_FORCE can
++	  be used, this is not a good option for kernels that are shared across
++	  devices. This setting enables using "chosen/cmdline-override" as the
++	  cmdline if it exists in the device tree.
++
+ config EFI_STUB
+ 	bool
+