test_lib: Correct calculation of number of processes
test_lib: Correct calculation of number of processes

Correct calculation of the number of parallel processes to use
when cover is used. It was supposed not to exceed 4 (according to
the comment), but it was calculated as the number of schedulers.

On my computer, having 8 schedulers, this change made the compiler
test suite with cover run almost twice as fast.

erlang/otp,ahmedshafeeq/otp,release-project/otp,jj1bdx/otp,massemanet/otp,massemanet/otp,cobusc/otp,g-andrade/otp,dumbbell/otp,lightcyphers/otp,massemanet/otp,psyeugenic/otp,mikpe/otp,bjorng/otp,RaimoNiskanen/otp,vinoski/otp,ahmedshafeeq/otp,emacsmirror/erlang,rlipscombe/otp,vinoski/otp,lightcyphers/otp,dumbbell/otp,bsmr-erlang/otp,rlipscombe/otp,legoscia/otp,goertzenator/otp,aboroska/otp,vladdu/otp,bjorng/otp,jj1bdx/otp,fenollp/otp,neeraj9/otp,dgud/otp,release-project/otp,neeraj9/otp,lrascao/otp,bsmr-erlang/otp,erlang/otp,tuncer/otp,kvakvs/otp,fenollp/otp,uabboli/otp,uabboli/otp,bernardd/otp,dumbbell/otp,uabboli/otp,lemenkov/otp,g-andrade/otp,ferd/otp,potatosalad/otp,mikpe/otp,isvilen/otp,isvilen/otp,erlang/otp,emile/otp,weisslj/otp,ahmedshafeeq/otp,cobusc/otp,rlipscombe/otp,RaimoNiskanen/otp,release-project/otp,lemenkov/otp,cobusc/otp,rlipscombe/otp,saleyn/otp,kvakvs/otp,bernardd/otp,g-andrade/otp,getong/otp,weisslj/otp,isvilen/otp,potatosalad/otp,falkevik/otp,release-project/otp,ferd/otp,aboroska/otp,mikpe/otp,basho/otp,erlang/otp,weisslj/otp,emile/otp,mikpe/otp,getong/otp,neeraj9/otp,lightcyphers/otp,lemenkov/otp,tuncer/otp,aboroska/otp,neeraj9/otp,aboroska/otp,bernardd/otp,bugs-erlang-org/otp,bjorng/otp,dgud/otp,RoadRunnr/otp,RaimoNiskanen/otp,potatosalad/otp,lrascao/otp,RoadRunnr/otp,jj1bdx/otp,fenollp/otp,uabboli/otp,aboroska/otp,bernardd/otp,potatosalad/otp,basho/otp,neeraj9/otp,bsmr-erlang/otp,rlipscombe/otp,emile/otp,vinoski/otp,emacsmirror/erlang,goertzenator/otp,isvilen/otp,RoadRunnr/otp,erlang/otp,aboroska/otp,legoscia/otp,RoadRunnr/otp,matwey/otp,saleyn/otp,emile/otp,dgud/otp,emacsmirror/erlang,legoscia/otp,tuncer/otp,uabboli/otp,vinoski/otp,emacsmirror/erlang,basho/otp,electricimp/otp,basho/otp,bjorng/otp,g-andrade/otp,getong/otp,bernardd/otp,emacsmirror/erlang,erlang/otp,electricimp/otp,basho/otp,RoadRunnr/otp,getong/otp,bugs-erlang-org/otp,emacsmirror/erlang,lemenkov/otp,tuncer/otp,saleyn/otp,goertzenator/otp,RoadRunnr/otp,matwey/otp,dumbbell/otp,legoscia/otp,mikpe/otp,psyeugenic/otp,falkevik/otp,isvilen/otp,bernardd/otp,emile/otp,kvakvs/otp,ferd/otp,dgud/otp,potatosalad/otp,vladdu/otp,erlang/otp,psyeugenic/otp,rlipscombe/otp,g-andrade/otp,saleyn/otp,lrascao/otp,ahmedshafeeq/otp,vladdu/otp,ahmedshafeeq/otp,lrascao/otp,matwey/otp,tuncer/otp,getong/otp,fenollp/otp,ahmedshafeeq/otp,bjorng/otp,kvakvs/otp,matwey/otp,RoadRunnr/otp,RaimoNiskanen/otp,falkevik/otp,emile/otp,falkevik/otp,basho/otp,jj1bdx/otp,isvilen/otp,basho/otp,fenollp/otp,erlang/otp,saleyn/otp,bjorng/otp,lemenkov/otp,aboroska/otp,vladdu/otp,weisslj/otp,dumbbell/otp,bugs-erlang-org/otp,weisslj/otp,goertzenator/otp,lemenkov/otp,jj1bdx/otp,fenollp/otp,electricimp/otp,jj1bdx/otp,massemanet/otp,matwey/otp,bernardd/otp,electricimp/otp,bsmr-erlang/otp,legoscia/otp,saleyn/otp,RaimoNiskanen/otp,bjorng/otp,matwey/otp,bugs-erlang-org/otp,dgud/otp,g-andrade/otp,vladdu/otp,ferd/otp,bsmr-erlang/otp,potatosalad/otp,massemanet/otp,uabboli/otp,release-project/otp,lrascao/otp,rlipscombe/otp,cobusc/otp,saleyn/otp,getong/otp,cobusc/otp,massemanet/otp,uabboli/otp,bernardd/otp,dumbbell/otp,cobusc/otp,ahmedshafeeq/otp,goertzenator/otp,electricimp/otp,aboroska/otp,emacsmirror/erlang,vladdu/otp,RaimoNiskanen/otp,release-project/otp,uabboli/otp,kvakvs/otp,psyeugenic/otp,neeraj9/otp,fenollp/otp,bsmr-erlang/otp,saleyn/otp,electricimp/otp,lemenkov/otp,getong/otp,kvakvs/otp,massemanet/otp,aboroska/otp,goertzenator/otp,vinoski/otp,bjorng/otp,jj1bdx/otp,lrascao/otp,ferd/otp,getong/otp,emacsmirror/erlang,lightcyphers/otp,tuncer/otp,weisslj/otp,potatosalad/otp,massemanet/otp,lightcyphers/otp,fenollp/otp,RaimoNiskanen/otp,release-project/otp,dgud/otp,matwey/otp,vladdu/otp,jj1bdx/otp,ferd/otp,vinoski/otp,psyeugenic/otp,mikpe/otp,emacsmirror/erlang,release-project/otp,rlipscombe/otp,erlang/otp,tuncer/otp,matwey/otp,emile/otp,bugs-erlang-org/otp,lrascao/otp,cobusc/otp,RaimoNiskanen/otp,kvakvs/otp,goertzenator/otp,getong/otp,bjorng/otp,bugs-erlang-org/otp,g-andrade/otp,RoadRunnr/otp,electricimp/otp,vinoski/otp,vinoski/otp,psyeugenic/otp,goertzenator/otp,lemenkov/otp,neeraj9/otp,emile/otp,bernardd/otp,dumbbell/otp,ferd/otp,falkevik/otp,lightcyphers/otp,kvakvs/otp,ferd/otp,lightcyphers/otp,lrascao/otp,psyeugenic/otp,isvilen/otp,dgud/otp,basho/otp,erlang/otp,legoscia/otp,saleyn/otp,tuncer/otp,bsmr-erlang/otp,massemanet/otp,weisslj/otp,ferd/otp,weisslj/otp,bsmr-erlang/otp,falkevik/otp,potatosalad/otp,dumbbell/otp,g-andrade/otp,bugs-erlang-org/otp,getong/otp,isvilen/otp,RoadRunnr/otp,uabboli/otp,dumbbell/otp,g-andrade/otp,cobusc/otp,rlipscombe/otp,falkevik/otp,jj1bdx/otp,electricimp/otp,isvilen/otp,emacsmirror/erlang,electricimp/otp,bugs-erlang-org/otp,ahmedshafeeq/otp,matwey/otp,lightcyphers/otp,vladdu/otp,vladdu/otp,g-andrade/otp,mikpe/otp,basho/otp,psyeugenic/otp,dumbbell/otp,ahmedshafeeq/otp,emile/otp,bsmr-erlang/otp,kvakvs/otp,lrascao/otp,goertzenator/otp,dgud/otp,vinoski/otp,jj1bdx/otp,weisslj/otp,falkevik/otp,potatosalad/otp,neeraj9/otp,legoscia/otp,dgud/otp,rlipscombe/otp,falkevik/otp,bjorng/otp,mikpe/otp,tuncer/otp,mikpe/otp,isvilen/otp,RaimoNiskanen/otp,legoscia/otp,fenollp/otp,release-project/otp,vinoski/otp,dgud/otp,mikpe/otp,legoscia/otp,potatosalad/otp