package/nxp-mwifiex: enable Linux option RTC_CLASS
Without Linux option RTC_CLASS enabled, the build fails with:
ERROR: modpost: "rtc_ktime_to_tm" [/home/sszy/development/eb972b781ead357c3e44a880cc1b8e4ab4b15b58/output/build/nxp-mwifiex-lf-6.6.52_2.2.0/./moal.ko] undefined!
Fix that by enbaling RTC_CLASS.
Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>