khadas-edge2: switch to rockchip-rk3588 legacy kernel; add bluetooth-hciattach for working bluetooth

- most of the work done by @monkaBlyat

config/boards/khadas-edge2.wip

@@ -1,20 +1,18 @@
 # Rockchip RK3588s 2GB-16GB GBE eMMC NVMe SATA USB3 WiFi
-BOARD_NAME="Khadas EDGE2"
-BOARDFAMILY="media"
-BOOT_SOC="rk3588"
-BOOTCONFIG="khadas-edge2-rk3588s_defconfig"
-KERNEL_TARGET="legacy"
-FULL_DESKTOP="yes"
-BOOT_LOGO="desktop"
-BOOT_FDT_FILE="rockchip/rk3588s-khadas-edge2.dtb"
-SRC_EXTLINUX="yes"
-SRC_CMDLINE="console=ttyS02,1500000 console=tty0"
-IMAGE_PARTITION_TABLE="gpt"
+declare -g BOARD_NAME="Khadas Edge2"
+declare -g BOARDFAMILY="rockchip-rk3588"
+declare -g BOOT_SOC="rk3588" # Just to avoid errors in rockchip64_commmon
+declare -g KERNEL_TARGET="legacy"
+declare -g IMAGE_PARTITION_TABLE="gpt"
+declare -g BOOT_FDT_FILE="rockchip/rk3588s-khadas-edge2.dtb" # Specific to this board
 
-function post_family_tweaks__khadas-edge-2-firmware() {
-    display_alert "$BOARD" "Installing board tweaks" "info"
+declare -g BLUETOOTH_HCIATTACH_PARAMS="-s 115200 /dev/ttyS9 bcm43xx 1500000" # For the bluetooth-hciattach extension
+enable_extension "bluetooth-hciattach"                                       # Enable the bluetooth-hciattach extension
 
-	cp -R $SRC/packages/blobs/station/firmware/* $SDCARD/lib/firmware/
-
-	return 0
+# for the kedge2, we're counting on the blobs+u-boot in SPI working, as it comes from factory. It does not support bootscripts.
+function post_family_config_branch_legacy__uboot_kedge2() {
+	display_alert "$BOARD" "Configuring ($BOARD) non-u-boot" "info"
+	unset BOOTSOURCE
+	declare -g BOOTCONFIG='none'
+	declare -g SRC_EXTLINUX="yes" # For now, use extlinux. Thanks Monka
 }