poppler: set ENV.cxx11 on < Mavericks
poppler: set ENV.cxx11 on < Mavericks

Apparently Poppler needs a bit of a nudge on the older
compilers that do support cxx11, otherwise you get weird linking failures when
other formulae that need cxx11 try to link to `-lpoppler`.

Closes #50170.

getgauge/homebrew,BrewTestBot/homebrew,dericed/homebrew,booi/homebrew,emcrisostomo/homebrew,marcwebbie/homebrew,yumitsu/homebrew,sakra/homebrew,sjackman/linuxbrew,Homebrew/homebrew,marcwebbie/homebrew,OJFord/homebrew,Angeldude/linuxbrew,nandub/homebrew,SuperNEMO-DBD/cadfaelbrew,skinny-framework/homebrew,Angeldude/linuxbrew,getgauge/homebrew,Homebrew/linuxbrew,influxdata/homebrew,sferik/homebrew,emcrisostomo/homebrew,dericed/homebrew,dickeyxxx/homebrew,deorth/homebrew,saketkc/linuxbrew,frodeaa/homebrew,ralic/homebrew,georgschoelly/homebrew,sometimesfood/homebrew,muellermartin/homebrew,pcottle/homebrew,pcottle/homebrew,gnubila-france/linuxbrew,influxdata/homebrew,gnubila-france/linuxbrew,booi/homebrew,sometimesfood/homebrew,3van/homebrew,liamstask/homebrew,dickeyxxx/homebrew,sakra/homebrew,marcwebbie/homebrew,mkrapp/homebrew,ExtremeMan/homebrew,influxdata/homebrew,pcottle/homebrew,SteveClement/homebrew,nandub/homebrew,OJFord/homebrew,sferik/homebrew,Homebrew/linuxbrew,afh/homebrew,mkrapp/homebrew,elgertam/homebrew,sakra/homebrew,sometimesfood/homebrew,skinny-framework/homebrew,ExtremeMan/homebrew,chadcatlett/homebrew,deorth/homebrew,optikfluffel/homebrew,reelsense/homebrew,Asuranceturix/homebrew,pcottle/homebrew,frodeaa/homebrew,cscetbon/homebrew,sferik/homebrew,dutchcoders/homebrew,emcrisostomo/homebrew,gnubila-france/linuxbrew,3van/homebrew,tutumcloud/homebrew,filcab/homebrew,marcwebbie/homebrew,tutumcloud/homebrew,sferik/homebrew,OJFord/homebrew,AlexejK/homebrew,ralic/homebrew,yumitsu/homebrew,joshfriend/homebrew,ilovezfs/homebrew,Asuranceturix/homebrew,benjaminfrank/homebrew,ExtremeMan/homebrew,afh/homebrew,josa42/homebrew,dplarson/homebrew,benjaminfrank/homebrew,mkrapp/homebrew,dutchcoders/homebrew,SteveClement/homebrew,Asuranceturix/homebrew,frodeaa/homebrew,optikfluffel/homebrew,SteveClement/homebrew,dickeyxxx/homebrew,tutumcloud/homebrew,brunchboy/homebrew,influxdb/homebrew,tschoonj/homebrew,Homebrew/linuxbrew,nandub/homebrew,quantumsteve/homebrew,josa42/homebrew,Homebrew/homebrew,benjaminfrank/homebrew,afh/homebrew,lrascao/homebrew,3van/homebrew,Linuxbrew/linuxbrew,SteveClement/homebrew,tschoonj/homebrew,reelsense/homebrew,deorth/homebrew,elgertam/homebrew,saketkc/linuxbrew,scorphus/homebrew,dutchcoders/homebrew,scorphus/homebrew,cscetbon/homebrew,dplarson/homebrew,ralic/homebrew,tschoonj/homebrew,Angeldude/linuxbrew,joshfriend/homebrew,chadcatlett/homebrew,booi/homebrew,dutchcoders/homebrew,tutumcloud/homebrew,skinny-framework/homebrew,reelsense/linuxbrew,frodeaa/homebrew,cscetbon/homebrew,3van/homebrew,totalvoidness/homebrew,SuperNEMO-DBD/cadfaelbrew,chadcatlett/homebrew,sjackman/linuxbrew,totalvoidness/homebrew,pcottle/homebrew,BrewTestBot/homebrew,BrewTestBot/homebrew,dericed/homebrew,yumitsu/homebrew,Linuxbrew/linuxbrew,scorphus/homebrew,Homebrew/homebrew,sakra/homebrew,brunchboy/homebrew,liamstask/homebrew,BrewTestBot/homebrew,reelsense/homebrew,theeternalsw0rd/homebrew,getgauge/homebrew,brunchboy/homebrew,base10/homebrew,filcab/homebrew,reelsense/linuxbrew,theeternalsw0rd/homebrew,optikfluffel/homebrew,theeternalsw0rd/homebrew,gawbul/homebrew,ExtremeMan/homebrew,Asuranceturix/homebrew,skinny-framework/homebrew,Angeldude/linuxbrew,gawbul/homebrew,saketkc/linuxbrew,sometimesfood/homebrew,ablyler/homebrew,AlexejK/homebrew,benjaminfrank/homebrew,muellermartin/homebrew,ilovezfs/homebrew,base10/homebrew,totalvoidness/homebrew,emcrisostomo/homebrew,dplarson/homebrew,lrascao/homebrew,filcab/homebrew,ablyler/homebrew,totalvoidness/homebrew,reelsense/linuxbrew,liamstask/homebrew,base10/homebrew,influxdb/homebrew,georgschoelly/homebrew,liamstask/homebrew,tschoonj/homebrew,joshfriend/homebrew,quantumsteve/homebrew,ablyler/homebrew,michaKFromParis/homebrew-sparks,AlexejK/homebrew,SuperNEMO-DBD/cadfaelbrew,Asuranceturix/homebrew,elgertam/homebrew,SuperNEMO-DBD/cadfaelbrew,influxdata/homebrew,sjackman/linuxbrew,gawbul/homebrew,theeternalsw0rd/homebrew,nandub/homebrew,quantumsteve/homebrew,AlexejK/homebrew,muellermartin/homebrew,scorphus/homebrew,ilovezfs/homebrew,reelsense/linuxbrew,Linuxbrew/linuxbrew,josa42/homebrew,ralic/homebrew,ilovezfs/homebrew,filcab/homebrew,dplarson/homebrew,brunchboy/homebrew,quantumsteve/homebrew,dickeyxxx/homebrew,Linuxbrew/linuxbrew,gnubila-france/linuxbrew,Homebrew/homebrew,michaKFromParis/homebrew-sparks,afh/homebrew,elgertam/homebrew,base10/homebrew,reelsense/homebrew,michaKFromParis/homebrew-sparks,getgauge/homebrew,SteveClement/homebrew,optikfluffel/homebrew,sjackman/linuxbrew,saketkc/linuxbrew,influxdb/homebrew,Homebrew/linuxbrew,georgschoelly/homebrew,georgschoelly/homebrew,muellermartin/homebrew,OJFord/homebrew,influxdb/homebrew,lrascao/homebrew,dericed/homebrew,ablyler/homebrew