Add entries for build products of OOM dump utility into .gitignore.

Review URL: http://codereview.chromium.org/6409008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6538 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

.gitignore

@@ -20,6 +20,8 @@ d8_g
 shell
 shell_g
 /obj/
+/tools/oom_dump/oom_dump
+/tools/oom_dump/oom_dump.o
 /tools/visual_studio/Debug
 /tools/visual_studio/Release
 /xcodebuild/