gitpkgv: Fix $GITPKV for a single named git source

Recipes that fetch from a single git source, assign a name to this
source and do not set SRCREV_FORMAT to this name will always get
a GITPKGV value of "default", which causes version-going-backwards QA
errors.

Fix this by automatically determining a suitable SRCREV_FORMAT from the
SRC_URI if none is set explicitly. This code does not run for multiple
git sources, because bitbake's fetcher enforces setting SRCREV_FORMAT
when multiple version-controlled sources are used.

Signed-off-by: Clemens Lang <clemens.lang@bmw-carit.de>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-oe/classes/gitpkgv.bbclass

@@ -61,7 +61,14 @@ def get_git_pkgv(d, use_tags):
     #
     format = d.getVar('SRCREV_FORMAT', True)
     if not format:
-        format = 'default'
+        names = []
+        for url in ud.values():
+            if url.type == 'git' or url.type == 'gitsm':
+                names.extend(url.revisions.keys())
+        if len(names) > 0:
+            format = '_'.join(names)
+        else:
+            format = 'default'
 
     found = False
     for url in ud.values():