drirc: Add "Second Life" quirk (allow_glsl_extension_directive_midshader).
Appears to fix shader compilation. Tested by starting the client,
dragging the "quality and speed" slider back and forth, and watching the
console output - instead of piles of "shader failed to compile", the CPU
seems to be busy compiling shaders. I haven't actually tried to play.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=69226
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71591
Cc: mesa-stable@lists.freedesktop.org