s/Intrin.h/intrin.h/, trying to fix the build after r272701

llvm-svn: 272702
diff --git a/clang/test/CodeGen/ms-mm-align.c b/clang/test/CodeGen/ms-mm-align.c
index 49feddd..7130c74 100644
--- a/clang/test/CodeGen/ms-mm-align.c
+++ b/clang/test/CodeGen/ms-mm-align.c
@@ -2,10 +2,10 @@
 // RUN:         -triple i686--windows -emit-llvm %s -o - \
 // RUN:         | FileCheck %s -check-prefix CHECK
 
-// Intrin.h needs size_t, but -ffreestanding prevents us from getting it from
+// intrin.h needs size_t, but -ffreestanding prevents us from getting it from
 // stddef.h.  Work around it with this typedef.
 typedef __SIZE_TYPE__ size_t;
-#include <Intrin.h>
+#include <intrin.h>
 
 void capture_ptr(int* i);
 void test_mm_align16(int p) {