dma-mapping: add <asm/dma-mapping.h> for all architectures

To avoid "asm/dma-mapping.h: No such file or directory" error,
we need something.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

arch/arc/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/m68k/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/microblaze/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/mips/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/powerpc/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/sandbox/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/sh/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */

arch/xtensa/include/asm/dma-mapping.h

+/* SPDX-License-Identifier: GPL-2.0-only */