platform/x86:intel/pmc: Improve function to show substate header

platform/x86:intel/pmc: Improve function to show substate header

Refactor pmc_core_substate_req_header_show() to accept a new argument.
This is a preparation patch to introduce a new way to show Low Power
Mode substate requirement data for platforms starting from Panther
Lake. Increased the size for the name column as the Low Power Mode
requirement register name is longer in newer platforms.

Signed-off-by: Xi Pardee <xi.pardee@linux.intel.com>
Link: https://patch.msgid.link/20250910210629.11198-4-xi.pardee@linux.intel.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>