msdkh265enc: output main-10 bitstream if the input is P010_10LE

Tested on KBL using the following command:
gst-launch-1.0 videotestsrc num_buffers=100 ! video/x-raw,format=P010_10LE ! \
msdkh265enc ! filesink location=a.hevc

This fixes gstreamer/gst-plugins-bad#829
9 jobs for hevc10-enc in 80 minutes and 27 seconds (queued for 54 minutes and 41 seconds)
Status Name Job ID Coverage
  Preparation
passed gst indent #61504

00:00:27

passed manifest #61503

00:00:22

 
  Build
passed build fedora x86_64 #61505

00:03:36

 
  Test
passed check fedora #61506

00:16:11

 
  Full Builds
passed build android arm64 api28 #61507

00:04:28

passed build cerbero fedora x86_64 #61653

00:55:21

failed build cerbero fedora x86_64 #61508

01:00:00

passed build cerbero fedora x86_64 #61625

00:55:12

failed build cerbero fedora x86_64 #61628

00:01:53