regulator: qcom-rpmh: Fix W=1 build warning when CONFIG_OF=n

regulator: qcom-rpmh: Fix W=1 build warning when CONFIG_OF=n

Fix below warning when CONFIG_OF=n:

drivers/regulator/qcom-rpmh-regulator.c:970:34: warning: ‘rpmh_regulator_match_table’ defined but not used [-Wunused-const-variable=]
  970 | static const struct of_device_id rpmh_regulator_match_table[] = {
      |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Link: https://lore.kernel.org/r/20200821111913.1096f7cc@xhacker.debian
Signed-off-by: Mark Brown <broonie@kernel.org>