wifi: iwlwifi: mvm: tx: remove misleading if statement

The if statement here is misleading, we return zero anyway
since we just checked the 'ret' variable, simplify the code
to remove the condition entirely.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230414130637.57c1eb58e655.I1b47a7771cd66306931089c150c6b5b240bdcba5@changeid


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