oe-build-perf-report: Allow branch without hostname

Allow the branch to be set without the hostname option. Previously
if hostname wasn't set, branch would be overwritten regardless of
whether it was set or not.

(From OE-Core rev: 3ec43bf4c6c8f7730a67f63ad4e14903f289014e)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/oe-build-perf-report

@@ -512,10 +512,10 @@ def auto_args(repo, args):
 
         key = split[0]
         val = split[1].strip()
-        if key == 'hostname':
+        if key == 'hostname' and not args.hostname:
             log.debug("Using hostname %s", val)
             args.hostname = val
-        elif key == 'branch':
+        elif key == 'branch' and not args.branch:
             log.debug("Using branch %s", val)
             args.branch = val