mesa: allow GL names reuse

Mesa uses a simple GL name picking algorithm: it returns the max used name + 1 (if it's < UINT32_MAX).

Some proprietary drivers, at least amdgpu-pro but I think nvidia too, recycle names instead and return the smaller non-in-use name.

So a create-delete-create sequence would return 1 then 2 with Mesa but 1 and 1 for proprietary drivers.

Both are correct but some applications depend on the "recycling" behavior (see #3144 (closed) for an example) so this MR adds support for name recycling in Mesa.

It can be enabled using the force_gl_names_reuse driconf option (and this MR enabled it for SPECviewperf 13).