Fix comment typo.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@166246 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/make/platform/clang_darwin.mk b/make/platform/clang_darwin.mk
index 3e331df..db128cf 100644
--- a/make/platform/clang_darwin.mk
+++ b/make/platform/clang_darwin.mk
@@ -77,7 +77,7 @@
 UniversalArchs.asan_osx_dynamic := $(call CheckArches,i386 x86_64,asan_osx_dynamic)
 
 # Darwin 10.6 has a bug in cctools that makes it unable to use ranlib on our ARM
-# object files. Of we are on that platform, we strip out all ARM archs. We still
+# object files. If we are on that platform, strip out all ARM archs. We still
 # build the libraries themselves so that Clang can find them where it expects
 # them, even though they might not have an expected slice.
 ifneq ($(shell sw_vers -productVersion | grep 10.6),)