Ensure two if statements only get executed if pEntry->pTexture isn't null.

Before it would access pEntry->pTexture regardless.
Remove an identical check in the same if-statement.

TLutFmt is already checked in the 8-th conditional.
Prefer -mt-less boost libraries by default
The newest boost version (1.5x) completely stripped the -mt suffix from the
libraries. This seems to be the default now and was already supported in
earlier versions (1.4x). Users requiring the suffix can still add them using
BOOST_SUFFIX and BOOST_THREAD_SUFFIX.
Fix mupen64plus OSD by disabling fragment shaders
Glitch64 uses fragment shaders extensively to emulate combiners. These also
affect external parts in other components of the emulator. Disabling them
before returning to the emulator should fix for example the OSD.
Use parentheses between '|' operations
GCC produces warnings when the statement is to confusing for the reader and
misinterpretations could happen. These can be avoided by adding parentheses to
clarify the statement.
Remove unused functions from HQ2x filters
Remove unused variables
Fix printf-format length errors in UpdateScreen
fix apparent vertex index calculation bug found by Lioncash
Reduce GHQTexInfo struct size from 44 bytes to 40 bytes.
Allow to build without GlideHQ support
Some systems don't have the required boost support and would not be able to
compile glide64 without adding a lot of new dependencies to their build
environment.
Remove warning about wxDynamicLibrary
The Glitch64 library is now part of glide64mk2 and it doesn't need to check the
symbols of an external library. Therefore, no wxDynamicLibrary is needed.
gles2rice: Merge 'upstream/video-rice' hg:1b2906a410791048e7a3fc91528f1678b4ffc79f
gles2glide64: Merge 'upstream/video-glide64mk2' hg:97a462e7925578dbb05e98b5dbd3ffa95c2a9130