glsl: default to compat shaders in compat profile
If the shader does not specify "core" or "compatibility" in shaders above 1.40 we were defaulting these shaders to core shaders when in a compat profile. Instead default to compat shaders.
This brings us inline with the behaviour of the binary drivers and fixes a crash on start-up for the game Foundation.
Closes: #3594 (closed)
Fixes: c7e3d31b ("glsl: fix compat shaders in GLSL 1.40")