jpeg2000parse: fix critical log when play one gray colorspace video
Need guess color space based on number of components when cannot got it from sink caps
/GstURIDecodeBin:uridecodebin0/GstDecodeBin:decodebin0/GstJPEG2000Parse:jpeg2000parse0.GstPad:sink: caps = image/x-j2c, width=(int)1024, height=(int)768, framerate=(fraction)1/1
** (gplay-1.0:2155): CRITICAL **: 03:52:12.515: gst_jpeg2000_sampling_to_string: assertion 'sampling > 0 && sampling <= G_N_ELEMENTS (gst_jpeg2000_sampling_strings)' failed
Edited by Haihua Hu