wifi: mwifiex: Use max_t() to improve code

Use max_t() to reduce the code and improve its readability.

Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Reviewed-by: Jeff Chen <jeff.chen_1@nxp.con>
Link: https://patch.msgid.link/20250715121721.266713-6-rongqianfeng@vivo.com


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