pending.py: skip PRs that are not based on the master branch

Only merge together the PRs that are based on the master branch.
There shouldn't be any PRs not based on the master branch, but if that
happens for any reason then skip them.
Signed-off-by: Guillaume Tucker <guillaume.tucker@collabora.com>

pending.py

@@ -81,6 +81,8 @@ def main(args):
             print_color('red', "SKIP untrusted user")
         elif (user, branch) in skip:
             print_color('yellow', "SKIP")
+        elif pr.base.ref != args.master:
+            print_color('yellow', "SKIP {}".format(pr.base.ref))
         else:
             if pull(args, pr, path):
                 print_color('green', "OK")
@@ -111,6 +113,8 @@ Create staging.kernelci.org branch with all pending PRs")
                         help="Tag to create, default is to use current date")
     parser.add_argument("--branch", default="staging.kernelci.org",
                         help="Name of the branch to force-push to")
+    parser.add_argument("--master", default="master",
+                        help="Name of the master branch to filter PRs")
     parser.add_argument("--namespace", default='kernelci',
                         help="Github project namespace")
     parser.add_argument("--skip", nargs='+', default=[],