sh: move sh asm/clock.h contents to linux/sh_clk.h V2

This patch is V2 of the clock framework move from
arch/sh/include/asm/clock.h to include/linux/sh_clk.h
and updates the include paths for files that will be
shared between SH and SH-Mobile ARM.

The file asm/clock.h is still kept in this version,
this to depend on as few files as possible at this
point. We keep SH specific stuff in there.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>