OPP: Remove doc style comments for internal routines

OPP: Remove doc style comments for internal routines

These were previously exposed outside of the OPP core and needed doc
style commenting. They aren't public now and don't need the same.

This fixes warnings generated for builds with `W=1`:

core.c:2105: warning: Function parameter or member 'opp_table' not described in '_opp_set_supported_hw'
core.c:2105: warning: Excess function parameter 'dev' description in '_opp_set_supported_hw'
core.c:2148: warning: Function parameter or member 'opp_table' not described in '_opp_set_prop_name'
core.c:2148: warning: Excess function parameter 'dev' description in '_opp_set_prop_name'
core.c:2189: warning: Function parameter or member 'opp_table' not described in '_opp_set_regulators'
core.c:2189: warning: Excess function parameter 'count' description in '_opp_set_regulators'
core.c:2293: warning: Function parameter or member 'opp_table' not described in '_opp_set_clknames'
core.c:2293: warning: Function parameter or member 'config_clks' not described in '_opp_set_clknames'
core.c:2391: warning: Function parameter or member 'opp_table' not described in '_opp_set_config_regulators_helper'
core.c:2455: warning: Function parameter or member 'opp_table' not described in '_opp_attach_genpd'
core.c:2682: warning: Function parameter or member 'token' not described in 'dev_pm_opp_clear_config'
core.c:2682: warning: Excess function parameter 'opp_table' description in 'dev_pm_opp_clear_config'

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309091558.x3JJrxFI-lkp@intel.com/
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>