runqemu-extract-sdk: support tar.xz format

As the format "tar.xz" is included in the IMAGE_TYPES bitbake variable
as defined in meta/classes/image_types.bbclass, it should also be
possible to extract a rootfs that has been built using that format.

(From OE-Core rev: f813ca7b085c7ddf76a34932e2b3f5bc3372b239)

Signed-off-by: Dennis Menschel <menschel-d@posteo.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/runqemu-extract-sdk

@@ -53,6 +53,9 @@ if [[ ${SDK_ROOTFS_DIR:0:1} != "/" ]]; then
 fi
 
 TAR_OPTS=""
+if [[ "$ROOTFS_TARBALL" =~ tar\.xz$ ]]; then
+	TAR_OPTS="--numeric-owner -xJf"
+fi
 if [[ "$ROOTFS_TARBALL" =~ tar\.bz2$ ]]; then
 	TAR_OPTS="--numeric-owner -xjf"
 fi
@@ -64,7 +67,7 @@ if [[ "$ROOTFS_TARBALL" =~ \.tar$ ]]; then
 fi
 if [ -z "$TAR_OPTS" ]; then
 	echo "Error: Unable to determine sdk tarball format"
-	echo "Accepted types: .tar / .tar.gz / .tar.bz2"
+	echo "Accepted types: .tar / .tar.gz / .tar.bz2 / .tar.xz"
 	exit 1
 fi