[examples] always build examples/platforms/utils (#3355)
[examples] always build examples/platforms/utils (#3355)


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