Add AVIF sniffing to ExifInterface

The exif metadata extraction process for AVIF is similar to HEIC.
Adding AVIF sniffing so that avif files can be used wit
ExifInterface.

CTS tests for this feature will come in a separate CL as there are
still some CLs in flight to finish AVIF support.

Test: ExifInterfaceTest still passes.
Bug: 141654151
Change-Id: I5546a4f81e928a29d46f6c4b9db77032a09a8350