Build modifications for MacOSX/Clang

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@60143 65644016-39b1-43b1-bf79-96bc8fe82c15
Fixed CORE-4586: connections to FB3 in "standaloneClassic" mode (firebird -s) hang up


git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@60144 65644016-39b1-43b1-bf79-96bc8fe82c15