QNX: Patch qcc-base-qnx.conf on Windows

There is a need to add

  -Wl,-rpath-link,$$[QT_INSTALL_LIBS]

on Windows to allow plugins to find their Qt dependencies.

Another workaround is to add

  CONFIG+=explicitlib create_prl

in the plugin's .pro file, but this means that all projects
having this problem will have to be modified, hence it's easier
to just patch our installers.

Change-Id: Ibd24db2418ef804d6cb12e84a1ac512ab54f47ec
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>