Lets not artificially cap the magnitude in the device specific
implementation.
Since the default magnitude for the common rumble feedback was set to
0.5 in the previous commit the effective magnitude in existing themes
remains unchanged for that event.
The pattern feedbacks didn't make it into a release yet so there's
nothing that could get broken.
The change doubles the effective when using the Vibra DBus API but as it
seems that libmanette didn't land support yet lets just ignore that
here.
Periodic feedback is unaffected as it uses a different internal API.
Signed-off-by: Guido Günther <agx@sigxcpu.org>