git: Tweak .gitignore to ignore defined platform build directories.
 - We should probably sink the platform build dirs into a common top-level dir.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@144662 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/.gitignore b/.gitignore
index 8f99959..7c53431 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
 *~
-Debug
-Release
-Profile
+darwin_fat
+clang_darwin
+multi_arch