Change lockscreen widgets to be 3-up on mobile.

With this change, widgets will be larger and take up more space on the
lockscreen in a 3-up configuration in portrait.

Open issues:

1. Widgets are 3-up in landscape as well, but are too small.
2. Widgets overlap edit mode buttons and the status text at the bottom
   of the screen.
3. Transitions into and out-of edit mode need to be repaired after this
   change.

Bug: 419357983
Test: manually
Flag: com.android.systemui.glanceable_hub_v2
Change-Id: Ic36f5e9fb7c055cbfbabacae4a0ffe8620cc034c