lib: s/drmtest_dumb_aub/igt_aub_dump_enabled/

This is prep work to extract a new igt aux library with all kinds
of random stuff. Also give it a bit a more suitable name to
indicate that this is just a flag and doesn't do the aub dumping
itself.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

tests/gem_render_copy.c

@@ -127,7 +127,7 @@ int main(int argc, char **argv)
 	igt_render_copyfunc_t render_copy = NULL;
 	int opt;
 	int opt_dump_png = false;
-	int opt_dump_aub = drmtest_dump_aub();
+	int opt_dump_aub = igt_aub_dump_enabled();
 
 	igt_simple_init();