[tilegx] Add various interfaces for TileGX.

  * try to fix those compile errors exposed by "make native"
    as much as possible

  * target-independent file "src/frame.h" modified, because TileGX
    has 64 registers, the original 32bit bitmap designed for
    x86/mips/arm is not enough.
[tilegx] Continue to add necessary interfaces to fix compiling errors.