Format if Encryption was Interrupted

If we're partially through setting up metadata encryption, failures
leave the partition in a known bad state, and we can avoid an eventual
boot into recovery by taking the format path.

Bug: 351704691
Test: Inserted debug code to reboot during initial encryption setup
      Verified device boots successfully on second attempt
Change-Id: I2d8591fa68ab0656e42b7b12f69001a5897e1a61