libfscrypt: Do not encrypt the "gsi" folder.

On FBE devices without metadata encryption, GSI images must not be
encrypted, since they are written using normal write() calls rather than
going through device-mapper.

Bug: 126249541
Test: GSI works on FBE device without metadata encryption
Change-Id: Ie14be778eb4a7f18dd8ea33a044ba86f909f3cce
1 file changed