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>
diff --git a/tests/gem_concurrent_blit.c b/tests/gem_concurrent_blit.c
index 03acf89..6a89aac 100644
--- a/tests/gem_concurrent_blit.c
+++ b/tests/gem_concurrent_blit.c
@@ -44,13 +44,16 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/wait.h>
-#include "drm.h"
+
+#include <drm.h>
+
 #include "ioctl_wrappers.h"
 #include "drmtest.h"
 #include "intel_bufmgr.h"
 #include "intel_batchbuffer.h"
 #include "intel_io.h"
 #include "intel_chipset.h"
+#include "igt_aux.h"
 
 static void
 prw_set_bo(drm_intel_bo *bo, uint32_t val, int width, int height)