Add a missing break.

Change-Id: I459bb15a59dbdae7619b108099f49c2a0c89ecc8
Reviewed-on: https://swiftshader-review.googlesource.com/3281
Tested-by: Ping-Hao Wu <pinghao@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
diff --git a/src/Main/FrameBuffer.cpp b/src/Main/FrameBuffer.cpp
index 37e9208..a2f9d52 100644
--- a/src/Main/FrameBuffer.cpp
+++ b/src/Main/FrameBuffer.cpp
@@ -489,6 +489,7 @@
 							d += dBytes;
 						}
 					}
+					break;
 				case FORMAT_R8G8B8:
 					{
 						For(Int x = x0, x < width, x++)