MIPS startup code:
- Removed tabs.
- Removed nonsense code involving $s7.
+ Call finalization procedure in the end, fixes webtbs/tw9089.
+ added non-executable stack marker.


git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@23842 3ad0048d-3df7-0310-abae-a5850022a9f2