clocksource/drivers: Fix various !CONFIG_HAS_IOMEM build errors

Fix !CONFIG_HAS_IOMEM related build failures in three clocksource drivers.

The build failures have the pattern of:

  drivers/clocksource/sh_cmt.c: In function ‘sh_cmt_map_memory’: drivers/clocksource/sh_cmt.c:920:2:
  error: implicit declaration of function ‘ioremap_nocache’ [-Werror=implicit-function-declaration]   cmt->mapbase = ioremap_nocache(mem->start, resource_size(mem));

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: maxime.ripard@free-electrons.com
Link: http://lkml.kernel.org/r/1427362029-6511-1-git-send-email-daniel.lezcano@linaro.org


Signed-off-by: Ingo Molnar <mingo@kernel.org>