i965: Rename INTEL_DEBUG=vec4vs to INTEL_DEBUG=vec4.
i965: Rename INTEL_DEBUG=vec4vs to INTEL_DEBUG=vec4.

driParseDebugString() doesn't have actual code to parse comma separated
lists (or any other supported options?); instead it dumbly uses strstr().

This means that INTEL_DEBUG="vec4vs" will trigger both DEBUG_VEC4VS and
DEBUG_VS, as "vs" is also a substring.

We should probably improve the driconf parsing, but for now, just rename
the option so it's usable in the meantime.

Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Acked-by: Jason Ekstrand <b186559eaedf698788888c8a2559b4efb4db10d6@intel.com>
Acked-by: Kristian Høgsberg <ca9b5b1e27d4fa7f4ba6848bdd08ca52cfd6330c@bitplanet.net>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler