* i8086 specific code from tcgpointerconstnode.pass_generate_code moved to an i8086 specific overriden method

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24577 3ad0048d-3df7-0310-abae-a5850022a9f2
* far pointer helper types made global in the implementation of the system unit

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24578 3ad0048d-3df7-0310-abae-a5850022a9f2