mesa: Fix incorrect access parameter passed to MapBuffer

The code previously passed GL_DYNAMIC_DRAW for the access parameter.
By inspection, I believe that all drivers would treat this as
GL_READ_WRITE because it's not GL_READ_ONLY and it's not
GL_WRITE_ONLY.

It appears the i965 code wants GL_WRITE_ONLY (it's about to write a
bunch of data in, never read data), while the arrayelt code is
GL_READ_ONLY (just dereffed as arguments to CALL_Whatever*v).

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Acked-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Keith Whitwell <keithw@vmware.com>

src/mesa/drivers/dri/i965/brw_draw_upload.c

@@ -689,9 +689,7 @@ static void brw_prepare_indices(struct brw_context *brw)
        * rebase it into a temporary.
        */
        if ((get_size(index_buffer->type) - 1) & offset) {
-           GLubyte *map = ctx->Driver.MapBuffer(ctx,
-                                                GL_DYNAMIC_DRAW_ARB,
-                                                bufferobj);
+           GLubyte *map = ctx->Driver.MapBuffer(ctx, GL_WRITE_ONLY, bufferobj);
            map += offset;
 
 	   intel_upload_data(&brw->intel, map, ib_size, ib_type_size,

src/mesa/main/api_arrayelt.c

@@ -1602,9 +1602,7 @@ void _ae_map_vbos( struct gl_context *ctx )
       _ae_update_state(ctx);
 
    for (i = 0; i < actx->nr_vbos; i++)
-      ctx->Driver.MapBuffer(ctx,
-			    GL_DYNAMIC_DRAW_ARB,
-			    actx->vbo[i]);
+      ctx->Driver.MapBuffer(ctx, GL_READ_ONLY, actx->vbo[i]);
 
    if (actx->nr_vbos)
       actx->mapped_vbos = GL_TRUE;