+ enabled compilation of unit fgl on i8086-msdos

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24650 3ad0048d-3df7-0310-abae-a5850022a9f2
make a warning a note, so it compiles with -Sew

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24651 3ad0048d-3df7-0310-abae-a5850022a9f2
added a dummy implementation of GetLastOSError

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24652 3ad0048d-3df7-0310-abae-a5850022a9f2
disabled sockets unit, because it doesn't build ATM

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24653 3ad0048d-3df7-0310-abae-a5850022a9f2