When no table data was read from ACPI, then filling the data
and returning success here will fill zero values, which means
transmit power will be limited to 0 dBm. This is clearly not
intended.

Return an error from iwl_sar_geo_init() if there's no data to
fill into the command structure.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes: 78a19d52 ("iwlwifi: mvm: Read the PPAG and SAR tables at INIT stage")
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20220517120044.bc45923b74e9.Id2b4362234b7f8ced82c591b95d4075dd2ec12f4@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>