Change /build to /build* in top-level .gitignore.

Reviewers: beanz

Differential Revision: https://reviews.llvm.org/D65559

llvm-svn: 367641

.gitignore

@@ -22,7 +22,7 @@
 .DS_store
 
 # Nested build directory
-/build
+/build*
 
 #==============================================================================#
 # Explicit files to ignore (only matches one).