Team Arena's mpteam6 map has a shader textures/base_wall2/space_concrete
that contains an opaque stage, two non-lightmap blendfunc filter stages,
a blendfunc add stage, and a lightmap stage. The lightmap was attached
to all four of the non-lightmap stages causing the filter stages to
darken the lightmap multiple times.
Change setting up the lightall GLSL shader to only use lightmap if it's
the first stage or not a blendfunc filter stage. Now only the opaque
and blendfunc add stages of the mpteam6 shader use the lightmap.
Reported by Alexander Nadeau (wareya).
3d6aa05694