wifi(fix): use -D wext for kobo wpa_supplicant
wifi(fix): use -D wext for kobo wpa_supplicant

mihailim/koreader,Frenzie/koreader,pazos/koreader,mwoz123/koreader,robert00s/koreader,koreader/koreader,Markismus/koreader,poire-z/koreader,Hzj-jie/koreader,NiLuJe/koreader,NiLuJe/koreader,koreader/koreader,houqp/koreader,Frenzie/koreader,apletnev/koreader,lgeek/koreader,poire-z/koreader