glx: Convert generated code function pointer thunking

glx: Convert generated code function pointer thunking

We're meant not to call these by name due to ABI.  Rather than try to
generate a bunch of little stub functions that do the lookup, just
inline it all directly into the calling function.

This does not cache results.  That's fine, this is not a performance
path, and if we're atop WGL then we effectively have to do this every
time anyway because wglGetProcAddress results are context-dependent.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Jon TURNEY <jon.turney@dronecode.org.uk>