refactor: cast bool to int to silence compiler warning
refactor: cast bool to int to silence compiler warning

This fixes -Wbitwise-instead-of-logical compiler warnings:

node/interfaces.cpp:544:16: warning: use of bitwise '&' with boolean operands [-Wbitwise-instead-of-logical]
        return FillBlock(ancestor, ancestor_out, lock, active) & FillBlock(block1, block1_out, lock, active) & FillBlock(block2, block2_out, lock, active);
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                                                                                             &&
node/interfaces.cpp:544:16: note: cast one or both operands to int to silence this warning
node/interfaces.cpp:544:16: warning: use of bitwise '&' with boolean operands [-Wbitwise-instead-of-logical]
        return FillBlock(ancestor, ancestor_out, lock, active) & FillBlock(block1, block1_out, lock, active) & FillBlock(block2, block2_out, lock, active);
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                                               &&
node/interfaces.cpp:544:16: note: cast one or both operands to int to silence this warning
2 warnings generated.

A similar change was recently made to libsecp in commit 16d13221
for the same reason.

mm-s/bitcoin,GroestlCoin/bitcoin,MarcoFalke/bitcoin,instagibbs/bitcoin,fanquake/bitcoin,AkioNak/bitcoin,domob1812/namecore,jambolo/bitcoin,jambolo/bitcoin,fujicoin/fujicoin,andreaskern/bitcoin,dscotese/bitcoin,anditto/bitcoin,achow101/bitcoin,pataquets/namecoin-core,andreaskern/bitcoin,bitcoin/bitcoin,AkioNak/bitcoin,anditto/bitcoin,domob1812/namecore,jlopp/statoshi,kallewoof/bitcoin,ajtowns/bitcoin,particl/particl-core,mm-s/bitcoin,lateminer/bitcoin,fujicoin/fujicoin,kallewoof/bitcoin,bitcoinsSG/bitcoin,fanquake/bitcoin,domob1812/bitcoin,Xekyo/bitcoin,GroestlCoin/bitcoin,GroestlCoin/bitcoin,lateminer/bitcoin,achow101/bitcoin,jamesob/bitcoin,domob1812/bitcoin,instagibbs/bitcoin,jamesob/bitcoin,ajtowns/bitcoin,pataquets/namecoin-core,fanquake/bitcoin,andreaskern/bitcoin,tecnovert/particl-core,ajtowns/bitcoin,lateminer/bitcoin,GroestlCoin/GroestlCoin,fujicoin/fujicoin,fujicoin/fujicoin,namecoin/namecoin-core,anditto/bitcoin,bitcoin/bitcoin,sstone/bitcoin,anditto/bitcoin,namecoin/namecoin-core,domob1812/namecore,namecoin/namecoin-core,particl/particl-core,tecnovert/particl-core,GroestlCoin/GroestlCoin,bitcoinsSG/bitcoin,sstone/bitcoin,MarcoFalke/bitcoin,dscotese/bitcoin,sstone/bitcoin,sstone/bitcoin,namecoin/namecoin-core,particl/particl-core,bitcoin/bitcoin,andreaskern/bitcoin,MarcoFalke/bitcoin,achow101/bitcoin,particl/particl-core,Xekyo/bitcoin,domob1812/bitcoin,achow101/bitcoin,namecoin/namecoin-core,fanquake/bitcoin,AkioNak/bitcoin,mm-s/bitcoin,mm-s/bitcoin,fujicoin/fujicoin,bitcoinknots/bitcoin,particl/particl-core,bitcoinknots/bitcoin,tecnovert/particl-core,pataquets/namecoin-core,jambolo/bitcoin,instagibbs/bitcoin,namecoin/namecore,kallewoof/bitcoin,mm-s/bitcoin,anditto/bitcoin,instagibbs/bitcoin,namecoin/namecore,jambolo/bitcoin,instagibbs/bitcoin,fanquake/bitcoin,jambolo/bitcoin,namecoin/namecoin-core,bitcoinsSG/bitcoin,namecoin/namecore,particl/particl-core,jamesob/bitcoin,bitcoinknots/bitcoin,AkioNak/bitcoin,mruddy/bitcoin,lateminer/bitcoin,bitcoin/bitcoin,namecoin/namecore,andreaskern/bitcoin,kallewoof/bitcoin,mruddy/bitcoin,bitcoinsSG/bitcoin,ajtowns/bitcoin,achow101/bitcoin,domob1812/namecore,pataquets/namecoin-core,ajtowns/bitcoin,dscotese/bitcoin,sipsorcery/bitcoin,tecnovert/particl-core,mruddy/bitcoin,AkioNak/bitcoin,jamesob/bitcoin,MarcoFalke/bitcoin,kallewoof/bitcoin,GroestlCoin/bitcoin,bitcoinknots/bitcoin,sipsorcery/bitcoin,jlopp/statoshi,GroestlCoin/GroestlCoin,pataquets/namecoin-core,domob1812/bitcoin,jlopp/statoshi,bitcoinsSG/bitcoin,dscotese/bitcoin,tecnovert/particl-core,domob1812/namecore,pataquets/namecoin-core,ajtowns/bitcoin,Xekyo/bitcoin,GroestlCoin/GroestlCoin,tecnovert/particl-core,GroestlCoin/bitcoin,jambolo/bitcoin,domob1812/bitcoin,instagibbs/bitcoin,fanquake/bitcoin,bitcoinsSG/bitcoin,jlopp/statoshi,AkioNak/bitcoin,dscotese/bitcoin,domob1812/namecore,GroestlCoin/bitcoin,jamesob/bitcoin,lateminer/bitcoin,jlopp/statoshi,sstone/bitcoin,achow101/bitcoin,domob1812/bitcoin,sipsorcery/bitcoin,andreaskern/bitcoin,Xekyo/bitcoin,bitcoinknots/bitcoin,mruddy/bitcoin,GroestlCoin/GroestlCoin,lateminer/bitcoin,sipsorcery/bitcoin,mruddy/bitcoin,bitcoin/bitcoin,dscotese/bitcoin,Xekyo/bitcoin,namecoin/namecore,jlopp/statoshi,Xekyo/bitcoin,anditto/bitcoin,namecoin/namecore,MarcoFalke/bitcoin,sstone/bitcoin,mm-s/bitcoin,fujicoin/fujicoin,kallewoof/bitcoin,sipsorcery/bitcoin,sipsorcery/bitcoin,MarcoFalke/bitcoin,mruddy/bitcoin,GroestlCoin/GroestlCoin,bitcoin/bitcoin,jamesob/bitcoin