persist_data: handle locked db for SELECT

Parallel processes interacting with the persist_data db can quite easily
explode without this.

(Bitbake rev: b3d5432cff0ff28f4c8a5bcf10efa3e383b4fd4d)

Signed-off-by: Chris Larson <chris_larson@mentor.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

bitbake/lib/bb/persist_data.py

@@ -127,9 +127,7 @@ class PersistData:
         count = 0
         while True:
             try:
-                ret = self.cursor.execute(*query)
-                #print "Had to retry %s times" % count
-                return ret
+                return self.cursor.execute(*query)
             except sqlite3.OperationalError as e:
                 if 'database is locked' in str(e) and count < 500:
                     count = count + 1