Update some .S file headers.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@85262 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/i386/floatundidf.S b/lib/i386/floatundidf.S
index d9be853..943ec38 100644
--- a/lib/i386/floatundidf.S
+++ b/lib/i386/floatundidf.S
@@ -1,4 +1,4 @@
-//===-- floatundidf.s - Implement __floatundidf for i386 ------------------===//
+//===-- floatundidf.S - Implement __floatundidf for i386 ------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //