Fix up hide Volume key cursor control

I'm sorry but I broke the code while review had been in progress between http://review.cyanogenmod.org/#/c/26310/
and http://review.cyanogenmod.org/#/c/32108/

Now Volume key cursor control should be hidden as intended.

Change-Id: I697984f25e6a53af4ee0c95a9951a31c5116eb91