docs/GL3.txt: consolidate r600 GL4.1.
docs/GL3.txt: consolidate r600 GL4.1.

Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler