First try on using the raspi seeds for raspi image building.

debian/changelog

@@ -1,3 +1,11 @@
+livecd-rootfs (2.664.13) UNRELEASED; urgency=medium
+
+  * Remove some unused and unneeded imx6 code paths.
+  * Enable usage of the ubuntu-server-raspi task for raspi images
+    (LP: #1912498).
+
+ -- Łukasz 'sil2100' Zemczak <lukasz.zemczak@ubuntu.com>  Wed, 20 Jan 2021 15:43:18 +0100
+
 livecd-rootfs (2.664.12) focal; urgency=medium
 
   * riscv64: backport HiFive unleashed & cloud-image building support

live-build/auto/config

@@ -802,11 +802,21 @@ case $PROJECT in
 			add_task install minimal standard cloud-image
 			add_package install ubuntu-minimal
 			KERNEL_FLAVOURS=virtual
-		        case $ARCH in
+
-				armhf|arm64|ppc64el|powerpc)
+			case $ARCH+${SUBARCH:-} in
+				armhf+raspi|arm64+raspi)
+					# Generic Raspberry Pi images
+					COMPONENTS='main restricted universe multiverse'
+					add_task install ubuntu-server-raspi
+					add_package install u-boot-rpi u-boot-tools
+					BINARY_REMOVE_LINUX=false
+					;;
+
+				armhf*|arm64*|ppc64el*|powerpc*)
 					add_task install server
 					;;
 			esac
+
 		fi
 
 		BINARY_REMOVE_LINUX=false
@@ -869,6 +879,12 @@ case $SUBPROJECT in
 		;;
 esac
 
+case $ARCH in
+	armhf|arm64)
+		KERNEL_FLAVOURS="${SUBARCH:-$KERNEL_FLAVOURS}"
+		;;
+esac
+
 # we'll expand the base seed given here according to the STRUCTURE file, and
 # then look in all of the seeds found to see which snaps are seeded
 case $PROJECT:${SUBPROJECT:-} in
@@ -937,27 +953,6 @@ case $PROJECT in
 		;;
 esac
 
-case $ARCH in
-	armhf|arm64)
-		KERNEL_FLAVOURS="${SUBARCH:-$KERNEL_FLAVOURS}"
-		case $SUBARCH in
-			raspi)
-				# Generic Raspberry Pi images
-				COMPONENTS='main restricted universe multiverse'
-				add_package install linux-firmware-raspi2 u-boot-rpi flash-kernel u-boot-tools wpasupplicant
-				BINARY_REMOVE_LINUX=false
-				;;
-			imx6)
-				COMPONENTS='main restricted universe multiverse'
-				KERNEL_FLAVOURS=generic
-				add_package install flash-kernel u-boot-tools wpasupplicant
-				BINARY_REMOVE_LINUX=false
-				;;
-
-		esac
-		;;
-esac
-
 case $PROJECT:${SUBPROJECT:-} in
 	ubuntu-server:*|ubuntu-base:*)
 		OPTS="${OPTS:+$OPTS }--linux-packages=none --initramfs=none"