Remove unneeded code and code duplication, add comments.

live-build/auto/build

@@ -573,7 +573,7 @@ case $PROJECT:${SUBPROJECT:-} in
     if [ "$PROJECT:$SUBPROJECT" = "ubuntu-core:system-image" ]; then
       case $ARCH in
           armhf)
-            subarches="generic raspi2 raspi3"
+            subarches="generic raspi2"
             ;;
           arm64)
             subarches="generic dragonboard"
@@ -609,9 +609,7 @@ case $PROJECT:${SUBPROJECT:-} in
               fi
               ;;
             armhf)
-              if [ "$devarch" = "raspi2" ]; then
-                  linux_package="linux-image-raspi2"
-              elif [ "$devarch" = "raspi3" ]; then
+              if [ "$devarch" = "raspi2" ] || [ "$devarch" = "raspi3" ]; then
                   linux_package="linux-image-raspi2"
               fi
               ;;
@@ -903,6 +901,12 @@ case $SUBARCH in
 		;;
 
 	raspi2|raspi3)
+		# copy the kernel and initrd to a predictable directory for
+		# ubuntu-image consumption.  In some cases, like in pi2/3
+		# u-boot, the bootloader needs to contain the kernel and initrd,
+		# so during rootfs build we copy it over to a directory that
+		# ubuntu-image looks for and shoves into the bootloader
+		# partition.
 		UBOOT_BOOT="image/boot/uboot"
 
 		mkdir -p $UBOOT_BOOT

live-build/auto/config

@@ -801,17 +801,11 @@ case $ARCH in
 				add_package live ac100-tarball-installer
 				BINARY_REMOVE_LINUX=false
 				;;
-			raspi2)
+			raspi2|raspi3)
 				COMPONENTS='main restricted universe multiverse'
 				add_package install linux-firmware-raspi2 u-boot-rpi flash-kernel u-boot-tools
 				BINARY_REMOVE_LINUX=false
 				;;
-			raspi3)
-				COMPONENTS='main restricted universe multiverse'
-				KERNEL_FLAVOURS=raspi2
-				add_package install linux-firmware-raspi2 u-boot-rpi flash-kernel u-boot-tools
-				BINARY_REMOVE_LINUX=false
-				;;
 		esac
 		;;
 esac