[buildbot] phase1: prioritize tagged build requests

[LEDE Commits]

jow pushed a commit to buildbot.git, branch master:
https://git.lede-project.org/5dac682fd48da487710d4eb1aa51ffc969fde3a3

commit 5dac682fd48da487710d4eb1aa51ffc969fde3a3
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Mon Feb 6 13:41:47 2017 +0100

    phase1: prioritize tagged build requests
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 phase1/master.cfg | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/phase1/master.cfg b/phase1/master.cfg
index a8d6737..735d2d4 100644
--- a/phase1/master.cfg
+++ b/phase1/master.cfg
@@ -246,6 +246,12 @@ def GetCwd(props):
 	else:
 		return "/"
 
+def GetNextBuild(builder, requests):
+	for r in requests:
+		if r.properties and r.properties.hasProperty("tag"):
+			return r
+	return requests[0]
+
 def MakeEnv(overrides=None):
 	env = {
 		'CC': WithProperties("%(cc)s", cc=GetCC),
@@ -756,7 +762,7 @@ for target in targets:
 
 	from buildbot.config import BuilderConfig
 
-	c['builders'].append(BuilderConfig(name=target, slavenames=slaveNames, factory=factory))
+	c['builders'].append(BuilderConfig(name=target, slavenames=slaveNames, factory=factory, nextBuild=getNextBuild))
 
 
 ####### STATUS TARGETS