PPCA fixed attrib vertex array buffer bindings

I neglected to properly track the array buffer binding per fixed vertex
array client state.

Add in the missing functionality, along with related tests to cover the
change.
Add missing depthClamp transform state

In reviewing the spec tables for my vertex array state changes, I
realized that I had missed adding support for tracking
enabling/disabling GL_DEPTH_CLAMP as transform state in my change where
I added transform state tracking.

Add it in, with test coverage.
Merge branch 'fix_ppca_fixed_vertex_array_buffer' of https://github.com/adhoc-bobcat/regal
Optional pointer logging for wgl API.

X11 window manager state logging support added.
Do not auto-detect REGAL_SYS_GLX if REGAL_SYS_X11=0.
GL api database corrections for GL_VERSION_x_y.