clocksource/drivers/sh_cmt: Add R-Car Gen4 support

Add support for the R-Car Gen4 CMT types 0/1 which are the same as in
the previous two generations.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220713100603.3391-4-wsa+renesas@sang-engineering.com


Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>