Don't take the DPMS lock in DPMI.createPackageSuspendedDialogIntent

This method is called by AM with the lock held, so can't take the
DPMS lock.

It still takes a different lock, but we don't call into the external
world while holding this lock, so this is fine.

Bug 29242568

Change-Id: Idbecdd7d97385ca66c693903443471fdbae833e6