[IMAGES] OpenSPA 7.2 for DM920UHD

Updated to OE4.2 core

- Python 2.7.13
- Gstreamer 1.13.0
- Glibc 2.2.6
- Openssh 7.6
- Busybox 1.27
- Samba   4.6.7
- Openssl 1.0.2m
- Nfs Util 2.1.1
- Dropbear 2017.75
- Bitbake 1.37
- GCC bug fixes
- openSSL Security fixes