+ preparations for returning int64 in ax:bx:cx:dx on i8086

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24498 3ad0048d-3df7-0310-abae-a5850022a9f2
- rm tcg8086.g_maybe_got_init as it's of no use for the i8086

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24499 3ad0048d-3df7-0310-abae-a5850022a9f2
- rm NR_PIC_OFFSET_REG from i8086/cpubase.inc, because it isn't used (and shouldn't be used) on the i8086

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@24500 3ad0048d-3df7-0310-abae-a5850022a9f2