Reasons:
- the PlayBook NDK is old and its compiler does not keep up with newest
C++11 improvements inside Qt code.
- the PlayBook NDK diverges considerably from the standard BB10 NDK,
making it non-trivial to keep a common codebase.
- It's a defunct platform.
- Maintenance time is limited.
[ChangeLog][Platform Specific Changes] Removed BlackBerry PlayBook support.
Change-Id: Ia338aff55f4e4b747ebdecb0e1463a369a656c03
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Bernd Weimer <bernd.weimer@pelagicore.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>