PTE flag cleanup from http://svn.freebsd.org/base/user/jmallett/octeon
- Rename PTE_xx flags to match their MIPS names
- Use the new pte_set/test/clear macros uniformly, instead of a mixture
of mips_pg_xxx(), pmap_pte_x() macros and direct access.
- Remove unused macros and defines from pte.h and pmap.c
Discussed on freebsd-mips@
Approved by: rrs(mentor), jmallett