wifi: mt76: mt7921: fix incorrect type conversion for CLC command

clc->len is defined as 32 bits in length, so it must also be
operated on with 32 bits, not 16 bits.

Fixes: fa6ad88e ("wifi: mt76: mt7921: fix country count limitation for CLC")
Signed-off-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312112104.Zkc3QUHr-lkp@intel.com/


Signed-off-by: Felix Fietkau <nbd@nbd.name>