bitbake/cooker: Ensure delays are accurately transfered to the idle loops from runqueue

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

bitbake/lib/bb/cooker.py

@@ -672,7 +672,7 @@ class BBCooker:
                 return False
             if retval is True:
                 return True
-            return 0.5
+            return retval
 
         self.server.register_idle_function(buildFileIdle, rq)
 
@@ -709,7 +709,7 @@ class BBCooker:
                 return False
             if retval is True:
                 return True
-            return 0.5
+            return retval
 
         self.buildSetVars()