net/wireless: Delete unnecessary checks before the macro call “dev_kfree_skb”

[ Upstream commit 868ad21496020ef83d41fdeed3b0a63de2a3caa5 ]

The dev_kfree_skb() function performs also input parameter validation.
Thus the test around the shown calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Stable-dep-of: 0c1528675d7a ("wifi: iwlegacy: common: don't call dev_kfree_skb() under spin_lock_irqsave()")
Signed-off-by: Sasha Levin <sashal@kernel.org>