Adjusting margins and paddings for portrait shade on large screens

1. Notifications were too narrow as side margins didn't account for NSSL padding
2. Increasing padding for sw720dp-port so that notification scrim takes more space

Fixes: 222472648
Test: compare lockscreen and shade to specs
Change-Id: I92cf020bc4763a47b5e0f99bfd68b8eb1f5675d2