Allow rotation when display is half-folded

When in 'tabletop' or 'book' mode, allow the display to rotate
even if it is frozen. Then return to the previously locked rotation when
the device is unfolded.

Bug: 240146362
Test: locally tested + ran atest on DisplayRotationTests
Change-Id: I9869f5b070fecd7df70e08323dfacef8b883f470