MIPS: JZ4740: remove clock.h

MIPS: JZ4740: remove clock.h

The only thing remaining in arch/mips/jz4740/clock.h is declarations of
the jz4740_clock_{suspend,resume} functions. Move these to
arch/mips/include/asm/mach-jz4740/clock.h for consistency with similar
functions, and remove the redundant arch/mips/jz4740/clock.h header.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10156/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>