WIP: Clean glxinfo and in addition clinfo

Complete rework what I was think about glxinfo what is usefull for users and that's the result:

Only compile glxinfo and glxgears and remove debug what ended up in

flatpak list -d | grep GlxInfo

org.freedesktop.GlxInfo/x86_64/18.08 fdo-sdk-test-repo beb1dd5a08a3 - 130,0 kB user,current

----> A custom shell command created (in glxinfo.bst):

#!/bin/sh
echo "GLX renderer:"
glxinfo | grep ^OpenGL
echo -e "\nLLVM pipe:"
LIBGL_ALWAYS_SOFTWARE=1 glxinfo | grep LLVM | grep ^OpenGL

----> The LLVM isn't allways in the standard glxinfo.

flatpak run org.freedesktop.GlxInfo

GLX renderer:
OpenGL vendor string: X.Org
OpenGL renderer string: Radeon RX 580 Series (POLARIS10, DRM 3.27.0, 4.20.0-1-MANJARO, LLVM 7.0.0)
OpenGL core profile version string: 4.5 (Core Profile) Mesa 18.3.1
OpenGL core profile shading language version string: 4.50
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.5 (Compatibility Profile) Mesa 18.3.1
OpenGL shading language version string: 4.50
OpenGL context flags: (none)
OpenGL profile mask: compatibility profile
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 Mesa 18.3.1
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions:

LLVM pipe:
OpenGL renderer string: llvmpipe (LLVM 7.0, 128 bits)

----> The old files still exist for the future.