iwlwifi: mvm: don't iterate unadded vifs when handling FW SMPS req

We may not have all the interfaces added to the driver when we get the
THERMAL_DUAL_CHAIN_REQUEST notification from the FW, so instead of
iterating all vifs to update SMPS, iterate only the ones that are
already assigned.  The interfaces that were not assigned yet, will be
updated accordingly when we start using them.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Fixes: 2a7ce54c ("iwlwifi: mvm: honour firmware SMPS requests")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20220129105618.9416aade2ba0.I0b71142f89e3f158aa058a1dfb2517c8c1fa3726@changeid


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