[build] add platform udp build switch (#3450)
[build] add platform udp build switch (#3450)


chshu/openthread,erja-gp/openthread,erja-gp/openthread,turon/openthread,srickardti/openthread,lanyuwen/openthread,openthread/openthread,erja-gp/openthread,librasungirl/openthread,openthread/openthread,lanyuwen/openthread,bukepo/openthread,erja-gp/openthread,chshu/openthread,librasungirl/openthread,abtink/openthread,lanyuwen/openthread,jwhui/openthread,librasungirl/openthread,chshu/openthread,jwhui/openthread,turon/openthread,chshu/openthread,erja-gp/openthread,jwhui/openthread,srickardti/openthread,bukepo/openthread,srickardti/openthread,abtink/openthread,openthread/openthread,bukepo/openthread,chshu/openthread,openthread/openthread,abtink/openthread,bukepo/openthread,jwhui/openthread,erja-gp/openthread,lanyuwen/openthread,chshu/openthread,lanyuwen/openthread,abtink/openthread,lanyuwen/openthread,turon/openthread,librasungirl/openthread,turon/openthread,srickardti/openthread