Doc: Add documentation for new iOS variables in qmake manual

documentation of QMAKE_DEVELOPMENT_TEAM and
QMAKE_PROVISIONING_PROFILE

Change-Id: Id5854862e44387e31db40f574d85f88512c27f0c
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>