r600g: use HTILE allocator from SI

r600g: use HTILE allocator from SI

It's almost the same.

This enables tiling for HTILE. It also enables Hyper-Z for other texture
targets (1D, 1D_ARRAY, 2D_ARRAY, CUBE, CUBE_ARRAY, 3D, RECT).

2D array depth textures are tested by Unigine Sanctuary and my new piglit
test.

Acked-by: Michel Dänzer <michel.daenzer@amd.com>