wifi: iwlwifi: mvm: consider having one active link

Do not call iwl_mvm_mld_get_primary_link if only one link
is active.
In that case, the sole active link should be used.

iwl_mvm_mld_get_primary_link returns -1 if only one link
is active causing a warning.

Fixes: 8c9bef26 ("wifi: iwlwifi: mvm: d3: implement suspend with MLO")
Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240311081938.6c50061bf69b.I05b0ac7fa7149eabaa5570a6f65b0d9bfb09a6f1@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>