Since kvfree() already checks if its argument is NULL, an additional
check before calling kvfree() is unnecessary and can be removed.

Remove both and the following Coccinelle/coccicheck warnings reported by
ifnullfree.cocci:

  WARNING: NULL check before some freeing functions is not needed
  WARNING: NULL check before some freeing functions is not needed
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241007115131.1811-3-thorsten.blum@linux.dev