iwlwifi: remove iwl_validate_sar_geo_profile() export

Only iwlmvm uses this function and it's so simple that it's clearer if
it's spelled out in the code anyway, so remove it and add the check
where needed.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200926002540.9e2f296f5cfc.I4b2c025768b5ceff93a80ba0ae9ee7784d6d7402@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>