[libclc][NFC] Fix up inconsistent copyright headers

Some files were accidentally given two copyright headers. Another was
missing one. This commit also converts that file's dos line endings to
unix ones and reformats a comment.

Author: frasercrmck

libclc/clc/lib/clspv/integer/clc_mul_hi.cl

@@ -1,5 +1,12 @@
-/*
-Opt-out of libclc mul_hi implementation for clspv.
-clspv has an internal implementation that does not required using a bigger data size.
-That implementation is based on OpMulExtended which is SPIR-V specific, thus it cannot be written in OpenCL-C.
-*/
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// Opt-out of libclc mul_hi implementation for clspv.
+// clspv has an internal implementation that does not required using a bigger
+// data size. That implementation is based on OpMulExtended which is SPIR-V
+// specific, thus it cannot be written in OpenCL-C.

libclc/generic/include/clc/misc/shuffle.h

@@ -6,14 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-//===-- generic/include/clc/misc/shuffle.h ------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
 #define _CLC_SHUFFLE_DECL(TYPE, MASKTYPE, RETTYPE) \
   _CLC_OVERLOAD _CLC_DECL RETTYPE shuffle(TYPE x, MASKTYPE mask);
 

libclc/generic/include/clc/misc/shuffle2.h

@@ -6,14 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-//===-- generic/include/clc/misc/shuffle2.h ------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
 #define _CLC_SHUFFLE2_DECL(TYPE, MASKTYPE, RETTYPE) \
   _CLC_OVERLOAD _CLC_DECL RETTYPE shuffle2(TYPE x, TYPE y, MASKTYPE mask);
 

libclc/generic/lib/misc/shuffle.cl

@@ -6,14 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-//===-- generic/lib/misc/shuffle.cl ------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
 #include <clc/clc.h>
 
 #define _CLC_ELEMENT_CASES2(VAR) \

libclc/generic/lib/misc/shuffle2.cl

@@ -6,14 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-//===-- generic/lib/misc/shuffle2.cl ------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
 #include <clc/clc.h>
 
 #define _CLC_ELEMENT_CASES2(VAR) \