QNX: Fix segfault when deleting qrfcommserver

Change-Id: Iefb851c818303c5f8fe2ef783ccfee5d13bcf827
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
QNX: Change name of platform define to QT_QNX_BLUETOOTH

To be aligned with the bluez implementation

Change-Id: I8d3fbd0c23298f984e2c99cbf4131cf8fc0a0a64
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>