[build] removed duplicate from source file list (#2179)
[build] removed duplicate from source file list (#2179)


georgecpr/openthread,srickardti/openthread,jwhui/openthread,lanyuwen/openthread,xiaom-GitHub/openthread,bukepo/openthread,bukepo/openthread,pvanhorn/openthread,lanyuwen/openthread,aeliot/openthread,pvanhorn/openthread,erja-gp/openthread,erja-gp/openthread,aeliot/openthread,fbsder/openthread,georgecpr/openthread,jwhui/openthread,mszczodrak/openthread,chshu/openthread,gandreello/openthread,pvanhorn/openthread,chshu/openthread,LeZhang2016/openthread,lanyuwen/openthread,librasungirl/openthread,aeliot/openthread,LeZhang2016/openthread,openthread/openthread,chshu/openthread,gandreello/openthread,fbsder/openthread,gandreello/openthread,LeZhang2016/openthread,fbsder/openthread,srickardti/openthread,erja-gp/openthread,srickardti/openthread,turon/openthread,jwhui/openthread,LeZhang2016/openthread,fbsder/openthread,librasungirl/openthread,lanyuwen/openthread,vaas-krish/openthread,vaas-krish/openthread,aeliot/openthread,bukepo/openthread,turon/openthread,vaas-krish/openthread,abtink/openthread,fbsder/openthread,abtink/openthread,jwhui/openthread,turon/openthread,LeZhang2016/openthread,xiaom-GitHub/openthread,chshu/openthread,chshu/openthread,xiaom-GitHub/openthread,abtink/openthread,xiaom-GitHub/openthread,vaas-krish/openthread,mszczodrak/openthread,gandreello/openthread,librasungirl/openthread,fbsder/openthread,mszczodrak/openthread,vaas-krish/openthread,chshu/openthread,erja-gp/openthread,lanyuwen/openthread,lanyuwen/openthread,xiaom-GitHub/openthread,vaas-krish/openthread,turon/openthread,erja-gp/openthread,openthread/openthread,pvanhorn/openthread,georgecpr/openthread,abtink/openthread,erja-gp/openthread,openthread/openthread,mszczodrak/openthread,xiaom-GitHub/openthread,librasungirl/openthread,georgecpr/openthread,mszczodrak/openthread,gandreello/openthread,srickardti/openthread,aeliot/openthread,mszczodrak/openthread,LeZhang2016/openthread,aeliot/openthread,gandreello/openthread,georgecpr/openthread,bukepo/openthread,pvanhorn/openthread,openthread/openthread,georgecpr/openthread,pvanhorn/openthread