DiskStatsService: stop checking for full-disk encryption

Since FDE (Full Disk Encryption) is no longer supported,
StorageManager.isBlockEncrypted() now always returns false.
In preparation for removing this method entirely, stop calling it from
DiskStatsService.dump().

Bug: 208476087
Change-Id: I25701ccae37005b087b221c62a07fb956887807a
1 file changed