ARM: shmobile: Remove mach/clkdev.h

Move over ARCH_SHMOBILE_LEGACY to use the default legacy ARM
implementations of __clk_get() and __clk_put() in <asm/clkdev.h>
by deselecting HAVE_MACH_CLKDEV. This has the nice side effect
that <mach/clkdev.h> is no longer used and can be removed.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>