QNX: adapt SSL lib file name lookup heuristics

I.e. do not try to load file names that are not there anyhow. The
code would search for libcrypto.so.1.0.0 and libssl.so.1.0.0, while
on QNX the libs are called libcrypto.so and libssl.so, and there
are no symlinks with version numbers.

This saves ~ 45 ms in real apps (tested with Facebook, Twitter and
Foursquare), and ~ 24 ms at app startup in an isolated app without
GUI (difference maybe because threads are fighting for CPU or so).

Task-number: QTBUG-32548
(backport of commit 69b31f7b657a7ca611ad980c2974597de160598c)

Change-Id: I33e1c9e2c490b9c7f94aca06add8dc183cce083d
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>