Fix vtlb compiling for x86_64.
This has no functional change on x86_32, it's mostly just changing a few pointer to u32 conversions to uptr and sptr.

I can not yet confirm if this runs on x86_64, but compiling is enough of an issue currently.
Merge pull request #137 from Sonicadvance1/vtlb-64bit

Fix vtlb compiling for x86_64.