OpenSL ES: enable the plugin only on Android.

Removed the configure test to enable or not the plugin (which solves
the problem of the plugin not being built on Windows because of a bug
in QMake). Even though it should work on other OpenSL ES
implementations than the Android one, it hasn't been tested. Compile
and use the plugin only on Android for now.

Task-number: QTBUG-34275
Change-Id: I02d47c8be3be8163a17c68b44b8c4b18a218a3fe
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
Blackberry: Improve camera focus handling

Use different state variables for focus/exposure/whitebalance
locks and update the exposure and whitebalance variables explicitly,
since BB10 doesn't provide a status callback method as for focus.

Change-Id: Ie6ba8f6a2a27f317c39994d21be8549c99daef6d
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>