[Piglit] [PATCH 0/8] add infrastructure for GLES1 tests

[Chia-I Wu]

This series adds the cmake infrastructure to write GLES1 tests.  Most
of it are about rearranging sources for piglitutil so that they can be
compiled against GLES1 headers.

Patch 1 is not strictly part of this series, but it fixes a compile
error on my machine.  Patch 2-4 move the code in piglitutil around,
in preparation for GLES1 support.

Patch 5-7 add GLES1 support to piglitutil and the last patch adds the
cmake changes.  I am not very certain about patch 6.  It adds
piglit-util-gles1.c to piglitutil, which includes piglit-util-gles2.c!
I am not sure if that is a good practice.  It might be better to
rename piglit-util-gles2.c to piglit-util-gles.c and let
libpiglitutil_gles{1,2}.a share it.