Revert "cpufreq: rcar: Add support for R8A7795 SoC"

This reverts commit 034def59.

This is no longer needed since the following commit and to the best
of my knowledge is not relied on by any upstream DTS:

edeec420 (cpufreq: dt-platdev: Automatically create cpufreq
device with OPP v2)

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>