wifi: iwlwifi: mld: eliminate duplicate WIDE_ID in PPAG command handling

wifi: iwlwifi: mld: eliminate duplicate WIDE_ID in PPAG command handling

Extract the PER_PLATFORM_ANT_GAIN_CMD command ID into a local variable
to avoid duplicating WIDE_ID(PHY_OPS_GROUP, PER_PLATFORM_ANT_GAIN_CMD).

Signed-off-by: Pagadala Yesu Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20260320100746.7b7e6315e2cc.Icffcc47ac1e876708b6219a89fd546a018797d44@changeid