vp8_drop_encodedframe_overshoot: fix to return setting.

Make sure force_maxqp is set to 0 for return 0.

Change-Id: Ie7c57842637226e932a390e7080e5ebb99996da3
diff --git a/vp8/encoder/ratectrl.c b/vp8/encoder/ratectrl.c
index 10d3408..f3050d3 100644
--- a/vp8/encoder/ratectrl.c
+++ b/vp8/encoder/ratectrl.c
@@ -1601,7 +1601,9 @@
       cpi->force_maxqp = 0;
       return 0;
     }
+    cpi->force_maxqp = 0;
     return 0;
   }
+  cpi->force_maxqp = 0;
   return 0;
 }