vp9_firstpass.c: clean -wextra warnings
vp9_firstpass.c: clean -wextra warnings

Change-Id: Ic488fe6edbc119f475763d72a85809499df60106

ittiamvpx/libvpx-1,Distrotech/libvpx,mwgoldsmith/libvpx,zofuthan/libvpx,Maria1099/webm.libvpx,liqianggao/libvpx,reimaginemedia/webm.libvpx,iniwf/webm.libvpx,Suvarna1488/webm.libvpx,abwiz0086/webm.libvpx,jmvalin/aom,kim42083/webm.libvpx,mwgoldsmith/vpx,Maria1099/webm.libvpx,mwgoldsmith/libvpx,Laknot/libvpx,running770/libvpx,VTCSecureLLC/libvpx,iniwf/webm.libvpx,smarter/aom,jmvalin/aom,matanbs/vp982,Maria1099/webm.libvpx,matanbs/vp982,webmproject/libvpx,altogother/webm.libvpx,mwgoldsmith/vpx,jacklicn/webm.libvpx,shacklettbp/aom,Acidburn0zzz/webm.libvpx,lyx2014/libvpx_c,kalli123/webm.libvpx,matanbs/vp982,zofuthan/libvpx,ittiamvpx/libvpx,altogother/webm.libvpx,GrokImageCompression/aom,Acidburn0zzz/webm.libvpx,felipebetancur/libvpx,ittiamvpx/libvpx,Acidburn0zzz/webm.libvpx,thdav/aom,shareefalis/libvpx,ittiamvpx/libvpx,reimaginemedia/webm.libvpx,Topopiccione/libvpx,Maria1099/webm.libvpx,felipebetancur/libvpx,felipebetancur/libvpx,pcwalton/libvpx,WebRTC-Labs/libvpx,Maria1099/webm.libvpx,matanbs/vp982,running770/libvpx,mbebenita/aom,n4t/libvpx,VTCSecureLLC/libvpx,felipebetancur/libvpx,ittiamvpx/libvpx-1,mwgoldsmith/vpx,kleopatra999/webm.libvpx,iniwf/webm.libvpx,Acidburn0zzz/webm.libvpx,matanbs/webm.libvpx,n4t/libvpx,GrokImageCompression/aom,smarter/aom,kalli123/webm.libvpx,Topopiccione/libvpx,matanbs/webm.libvpx,zofuthan/libvpx,matanbs/webm.libvpx,shacklettbp/aom,WebRTC-Labs/libvpx,ShiftMediaProject/libvpx,Distrotech/libvpx,zofuthan/libvpx,goodleixiao/vpx,Topopiccione/libvpx,zofuthan/libvpx,n4t/libvpx,lyx2014/libvpx_c,abwiz0086/webm.libvpx,stewnorriss/libvpx,abwiz0086/webm.libvpx,VTCSecureLLC/libvpx,shareefalis/libvpx,ShiftMediaProject/libvpx,goodleixiao/vpx,mbebenita/aom,kleopatra999/webm.libvpx,kleopatra999/webm.libvpx,GrokImageCompression/aom,ittiamvpx/libvpx,mbebenita/aom,ittiamvpx/libvpx-1,abwiz0086/webm.libvpx,shacklettbp/aom,abwiz0086/webm.libvpx,charup/https---github.com-webmproject-libvpx-,kleopatra999/webm.libvpx,shyamalschandra/libvpx,Topopiccione/libvpx,reimaginemedia/webm.libvpx,smarter/aom,matanbs/vp982,goodleixiao/vpx,Laknot/libvpx,openpeer/libvpx_new,iniwf/webm.libvpx,luctrudeau/aom,Suvarna1488/webm.libvpx,luctrudeau/aom,pcwalton/libvpx,smarter/aom,webmproject/libvpx,thdav/aom,lyx2014/libvpx_c,felipebetancur/libvpx,mwgoldsmith/libvpx,Laknot/libvpx,Topopiccione/libvpx,webmproject/libvpx,liqianggao/libvpx,gshORTON/webm.libvpx,abwiz0086/webm.libvpx,shyamalschandra/libvpx,Suvarna1488/webm.libvpx,WebRTC-Labs/libvpx,kim42083/webm.libvpx,felipebetancur/libvpx,running770/libvpx,mwgoldsmith/libvpx,hsueceumd/test_hui,n4t/libvpx,shacklettbp/aom,reimaginemedia/webm.libvpx,shyamalschandra/libvpx,Acidburn0zzz/webm.libvpx,hsueceumd/test_hui,webmproject/libvpx,iniwf/webm.libvpx,liqianggao/libvpx,jacklicn/webm.libvpx,mbebenita/aom,ittiamvpx/libvpx-1,altogother/webm.libvpx,n4t/libvpx,jmvalin/aom,matanbs/vp982,gshORTON/webm.libvpx,shacklettbp/aom,gshORTON/webm.libvpx,altogother/webm.libvpx,mbebenita/aom,running770/libvpx,jmvalin/aom,pcwalton/libvpx,hsueceumd/test_hui,openpeer/libvpx_new,VTCSecureLLC/libvpx,lyx2014/libvpx_c,goodleixiao/vpx,liqianggao/libvpx,Laknot/libvpx,charup/https---github.com-webmproject-libvpx-,jdm/libvpx,hsueceumd/test_hui,kalli123/webm.libvpx,thdav/aom,Topopiccione/libvpx,VTCSecureLLC/libvpx,thdav/aom,kim42083/webm.libvpx,smarter/aom,Suvarna1488/webm.libvpx,charup/https---github.com-webmproject-libvpx-,stewnorriss/libvpx,webmproject/libvpx,pcwalton/libvpx,WebRTC-Labs/libvpx,ittiamvpx/libvpx-1,matanbs/webm.libvpx,jmvalin/aom,luctrudeau/aom,shareefalis/libvpx,kleopatra999/webm.libvpx,jdm/libvpx,ittiamvpx/libvpx-1,charup/https---github.com-webmproject-libvpx-,Distrotech/libvpx,shyamalschandra/libvpx,goodleixiao/vpx,gshORTON/webm.libvpx,shareefalis/libvpx,mbebenita/aom,Acidburn0zzz/webm.libvpx,pcwalton/libvpx,luctrudeau/aom,stewnorriss/libvpx,jacklicn/webm.libvpx,shyamalschandra/libvpx,openpeer/libvpx_new,WebRTC-Labs/libvpx,Suvarna1488/webm.libvpx,kim42083/webm.libvpx,mbebenita/aom,mwgoldsmith/libvpx,jdm/libvpx,mwgoldsmith/vpx,openpeer/libvpx_new,smarter/aom,liqianggao/libvpx,hsueceumd/test_hui,GrokImageCompression/aom,gshORTON/webm.libvpx,webmproject/libvpx,jdm/libvpx,ittiamvpx/libvpx,matanbs/vp982,thdav/aom,mbebenita/aom,kalli123/webm.libvpx,jacklicn/webm.libvpx,reimaginemedia/webm.libvpx,pcwalton/libvpx,kalli123/webm.libvpx,jdm/libvpx,matanbs/webm.libvpx,Suvarna1488/webm.libvpx,ShiftMediaProject/libvpx,kim42083/webm.libvpx,luctrudeau/aom,iniwf/webm.libvpx,mbebenita/aom,matanbs/webm.libvpx,jdm/libvpx,reimaginemedia/webm.libvpx,lyx2014/libvpx_c,luctrudeau/aom,mwgoldsmith/vpx,stewnorriss/libvpx,gshORTON/webm.libvpx,lyx2014/libvpx_c,GrokImageCompression/aom,shareefalis/libvpx,Distrotech/libvpx,running770/libvpx,Distrotech/libvpx,stewnorriss/libvpx,openpeer/libvpx_new,shacklettbp/aom,GrokImageCompression/aom,mwgoldsmith/vpx,hsueceumd/test_hui,kim42083/webm.libvpx,jacklicn/webm.libvpx,zofuthan/libvpx,Laknot/libvpx,altogother/webm.libvpx,mwgoldsmith/libvpx,altogother/webm.libvpx,openpeer/libvpx_new,good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