linux-raspberrypi: CMDLINE is not handled by a rpi-cmdline recipe

The BSP layer migrated to a separate recipe for cmdline: rpi-cmdline.
Align accordingly.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-oniro-core/recipes-bsp/bootfiles/rpi-cmdline.bbappend

+# SPDX-FileCopyrightText: Huawei Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# Make rootfstype defined based on ROOT_FSTYPE (selected by wic configuration)
+CMDLINE_ROOT_FSTYPE = "rootfstype=${ROOT_FSTYPE} ro"

meta-oniro-core/recipes-kernel/linux/linux-raspberrypi_%.bbappend

@@ -5,6 +5,3 @@
 FILESEXTRAPATHS:prepend := "${THISDIR}/linux:"
 
 SRC_URI += "file://squashfs.cfg"
-
-# Make rootfstype defined based on ROOT_FSTYPE (selected be wic configuration)
-CMDLINE = "dwc_otg.lpm_enable=0 ${SERIAL} root=/dev/mmcblk0p2 rootfstype=${ROOT_FSTYPE} rootwait ro"