iwlwifi: mvm: return the cooling state index instead of the budget

iwl_mvm_tcool_get_cur_state is the function that returns the
cooling state index to the sysfs handler. This function returns
mvm->cooling_dev.cur_state but that variable was set to the
budget and not the cooling state index. Fix that.
Add a missing blank line while at it.

Signed-off-by: Chaya Rachel Ivgi <chaya.rachel.ivgi@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>