lib: extract igt_aux.[hc]

And shovel all the various helpers in there.

Also move igt_set_vt_graphics_mode to igt_kms.h since the function is
implemented in igt_kms.c. And it fits better. I kinda missed this in
the prep work.

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

lib/igt_kms.h

@@ -164,6 +164,9 @@ struct igt_display {
 	igt_pipe_t pipes[I915_MAX_PIPES];
 };
 
+/* set vt into graphics mode, required to prevent fbcon from interfering */
+void igt_set_vt_graphics_mode(void);
+
 void igt_display_init(igt_display_t *display, int drm_fd);
 void igt_display_fini(igt_display_t *display);
 int  igt_display_commit(igt_display_t *display);