[buildbot] phase1: use a different name for the Git clone work directory

[LEDE Commits]

jow pushed a commit to buildbot.git, branch master:
https://git.lede-project.org/d5c7fd616e540c6c775101fc2312ab80c0d2ae64

commit d5c7fd616e540c6c775101fc2312ab80c0d2ae64
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Tue Nov 15 14:28:41 2016 +0100

    phase1: use a different name for the Git clone work directory
    
    Upon first start, the build master expects a clean directory to issue
    git init --bare in, therfore we cannot use the clone used for bootstrapping.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 phase1/master.cfg | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/phase1/master.cfg b/phase1/master.cfg
index 296e9fb..939649d 100644
--- a/phase1/master.cfg
+++ b/phase1/master.cfg
@@ -94,6 +94,9 @@ targets = [ ]
 if not os.path.isdir(home_dir+'/source.git'):
 	subprocess.call(["git", "clone", "--depth=1", repo_url, home_dir+'/source.git'])
 	subprocess.call(["git", "checkout", repo_branch], cwd = home_dir+'/source.git')
+else:
+	subprocess.call(["git", "checkout", repo_branch], cwd = home_dir+'/source.git')
+	subprocess.call(["git", "pull"], cwd = home_dir+'/source.git')
 
 findtargets = subprocess.Popen([home_dir+'/dumpinfo.pl', 'targets'],
 	stdout = subprocess.PIPE, cwd = home_dir+'/source.git')
@@ -113,7 +116,7 @@ from buildbot.changes.gitpoller import GitPoller
 c['change_source'] = []
 c['change_source'].append(GitPoller(
 	repo_url,
-	workdir=home_dir+'/source.git', branch='master',
+	workdir=home_dir+'/work.git', branch='master',
 	pollinterval=300))
 
 ####### SCHEDULERS