wifi: cw1200: Fix potential NULL dereference

A recent refactoring was identified by static analysis to
cause a potential NULL dereference, fix this!

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202410121505.nyghqEkK-lkp@intel.com/


Fixes: 2719a9e7 ("wifi: cw1200: Convert to GPIO descriptors")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/20241028-cw1200-fix-v1-1-e092b6558d1e@linaro.org