oe-build-perf-test: implement --commit-results-branch

A new command line option for defining the branch where results are
commited. The value is actually a format string accepting two field
names:
- {git_branch} expands to the name of the target branch being tested
- {tester_host} expands to the hostname of the tester machine

The option has no effect if --commit-results is not used.

(From OE-Core rev: b54b63395ec632748a57a702812c8a9a07af35ab)

Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/buildperf/base.py

@@ -193,6 +193,11 @@ class BuildPerfTestResult(unittest.TextTestResult):
         repo = GitRepo(repo_path, is_topdir=True)
         if not branch:
             branch = self.git_branch
+        else:
+            # Replace keywords
+            branch = branch.format(git_branch=self.git_branch,
+                                   tester_host=self.hostname)
+
         log.info("Committing test results into %s %s", repo_path, branch)
         tmp_index = os.path.join(repo_path, '.git', 'index.oe-build-perf')
         try: