mesa: remove MAX_VERTEX_PROGRAM_ATTRIBS

Use MAX_VERTEX_GENERIC_ATTRIBS instead.  No need for two #defines for
the same quantity.

src/mesa/tnl/t_vb_program.c

@@ -207,7 +207,7 @@ init_machine(GLcontext *ctx, struct gl_program_machine *machine)
 {
    /* Input registers get initialized from the current vertex attribs */
    MEMCPY(machine->VertAttribs, ctx->Current.Attrib,
-          MAX_VERTEX_PROGRAM_ATTRIBS * 4 * sizeof(GLfloat));
+          MAX_VERTEX_GENERIC_ATTRIBS * 4 * sizeof(GLfloat));
 
    if (ctx->VertexProgram._Current->IsNVProgram) {
       GLuint i;