Fix volume dialog size on the landscape phone

This change makes sure that the volume dialog fits the size of the screen when the vertical space is limited. For example, when the phone is in the landscape

Flag: com.android.systemui.volume_redesign
Bug: 369993959
Test: manual on the phone. Open the Volume Dialog when the phone is in
the landscape orientation and observe

Change-Id: I80586a9ac858451030e452908fed4c53e154cb08