package_manager.py: Use data.tar.xz for ipkg too

Commit b95b6ba1a2959e2294a8848fa35f20163388eb06 changed package_ipk.bbclass
to xz when building packages.  This updates OpkgDpkgPM.extract() accordingly.

(From OE-Core rev: c09a22c421a57701f6b943eb50b9bae1545e5b39)

Signed-off-by: Angus Lees <gus@inodes.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oe/package_manager.py

@@ -1118,10 +1118,7 @@ class OpkgDpkgPM(PackageManager):
         tmp_dir = tempfile.mkdtemp()
         current_dir = os.getcwd()
         os.chdir(tmp_dir)
-        if self.d.getVar('IMAGE_PKGTYPE') == 'deb':
-            data_tar = 'data.tar.xz'
-        else:
-            data_tar = 'data.tar.gz'
+        data_tar = 'data.tar.xz'
 
         try:
             cmd = [ar_cmd, 'x', pkg_path]
@@ -1530,7 +1527,7 @@ class OpkgPM(OpkgDpkgPM):
                      "trying to extract the package."  % pkg)
 
         tmp_dir = super(OpkgPM, self).extract(pkg, pkg_info)
-        bb.utils.remove(os.path.join(tmp_dir, "data.tar.gz"))
+        bb.utils.remove(os.path.join(tmp_dir, "data.tar.xz"))
 
         return tmp_dir