uvcvideo: Fix a wrong macro

uvcvideo: Fix a wrong macro

BugLink: http://bugs.launchpad.net/bugs/1673538
commit 17c341ec0115837a610b2da15e32546e26068234 upstream.

Don't mix up UVC_BUF_STATE_* and VB2_BUF_STATE_* codes.

Fixes: 6998b6fb4b1c ("[media] uvcvideo: Use videobuf2-vmalloc")
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@intel.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>