mesa: simplify dispatch for glDraw* functions

Remove all the glDraw* functions from the GLvertexformat structure.
The point of that dispatch struct is to handle all the functions which
dispatch differently depending on whether we're inside glBegin/End.
glDraw* are never allowed inside glBegin/End so we can remove those
entries.

This simplifies the code paths and gets rid of quite a bit of code.

Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

src/mapi/glapi/gen/gl_genexec.py

@@ -109,6 +109,7 @@ header = """/**
 #include "main/syncobj.h"
 #include "main/formatquery.h"
 #include "main/dispatch.h"
+#include "vbo/vbo.h"
 
 
 /**
@@ -128,6 +129,8 @@ _mesa_initialize_exec_table(struct gl_context *ctx)
    assert(exec != NULL);
 
    assert(ctx->Version > 0);
+
+   vbo_initialize_exec_dispatch(ctx, exec);
 """