wifi: iwlwifi: mvm: refactor iwl_mvm_roc()

wifi: iwlwifi: mvm: refactor iwl_mvm_roc()

This flow is almost the same for both MLD and non-MLD modes,
except for some function calls. Therefore there is no reason to
add an MLD version of this flow. Instead - put the parts that are unique
for each mode in helper functions, and in the next patch each version of
this flow will call the common part with pointers to its specific
helper functions.

Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230328104948.61bc077a7f3c.Ia3aa81d3293792bf8f80528dbc67a711ce334b32@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>