wifi: iwlwifi: fw: read STEP table from correct UEFI var

wifi: iwlwifi: fw: read STEP table from correct UEFI var

This variable exists for the "common" (WiFi/BT) GUID, not the
WiFi-only GUID. Fix that by passing the GUID to the function.
A short-cut for the wifi-only version remains so not all code
must be updated.

However, rename the GUID defines to be clearer.

Fixes: 09b4c35d73a5 ("wifi: iwlwifi: mvm: Support STEP equalizer settings from BIOS.")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Daniel Gabay <daniel.gabay@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20241227095718.89a5ad921b6d.Idae95a70ff69d2ba1b610e8eced826961ce7de98@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>