wifi: mac80211: scan: Use max macro

When the original file is guaranteed to contain the minmax.h header
file and compile correctly, using the real macro is usually
more intuitive and readable.

Signed-off-by: Yan Zhen <yanzhen@vivo.com>
Link: https://patch.msgid.link/20240827103012.3853588-1-yanzhen@vivo.com


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