devtool: finish/update-recipe: restrict mode srcrev to recipes fetched from SCM

When specifying --mode / -m srcrev with devtool finish/update-recipe on
recipes that are not fetched from a SCM repository we get the following
error:

  Traceback (most recent call last):
  [..]
    File "<...>/poky/meta/lib/oe/patch.py", line 49, in runcmd
    raise CmdError(cmd, exitstatus >> 8, "stdout: %s\nstderr: %s" % (stdout, stderr))
oe.patch.CmdError: Command Error: 'sh -c 'git format-patch --no-signature --no-numbered INVALID -o /tmp/oepatchbj7pfmzj -- .'' exited with 0  Output:
stdout:
stderr: fatal: bad revision 'INVALID'

Fix this by adding a check and abort with a proper error message.

(From OE-Core rev: 9254b08fbfba3734d5bc717a382d909595833db1)

Signed-off-by: Julien Stephan <jstephan@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 5b77f60e85d07921ae5e808daa1fd7d8c3dc40ea)
Signed-off-by: Steve Sakoman <steve@sakoman.com>

scripts/lib/devtool/standard.py

@@ -1530,6 +1530,11 @@ def _update_recipe_srcrev(recipename, workspace, srctree, rd, appendlayerdir, wi
     recipedir = os.path.basename(recipefile)
     logger.info('Updating SRCREV in recipe %s%s' % (recipedir, dry_run_suffix))
 
+    # Get original SRCREV
+    old_srcrev = rd.getVar('SRCREV') or ''
+    if old_srcrev == "INVALID":
+            raise DevtoolError('Update mode srcrev is only valid for recipe fetched from an SCM repository')
+
     # Get HEAD revision
     try:
         stdout, _ = bb.process.run('git rev-parse HEAD', cwd=srctree)
@@ -1556,7 +1561,6 @@ def _update_recipe_srcrev(recipename, workspace, srctree, rd, appendlayerdir, wi
         if not no_remove:
             # Find list of existing patches in recipe file
             patches_dir = tempfile.mkdtemp(dir=tempdir)
-            old_srcrev = rd.getVar('SRCREV') or ''
             upd_p, new_p, del_p = _export_patches(srctree, rd, old_srcrev,
                                                   patches_dir)
             logger.debug('Patches: update %s, new %s, delete %s' % (dict(upd_p), dict(new_p), dict(del_p)))