UPSTREAM: udf: Get rid of 0-length arrays in struct fileIdentDesc

Get rid of 0-length arrays in struct fileIdentDesc. This requires a bit
of cleaning up as the second variable length array in this structure is
often used and the code abuses the fact that the first two arrays have
the same type and offset in struct fileIdentDesc.

Signed-off-by: Jan Kara <jack@suse.cz>

Bug: 246669914
(cherry picked from commit 979a6e28)
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Change-Id: I453a0c44fe7358b30125acb715756ff7b8ac55aa