fs-verity: remove filenames from file comments

Embedding the file path inside kernel source code files isn't
particularly useful as often files are moved around and the paths become
incorrect.  checkpatch.pl warns about this since v5.10-rc1.

Acked-by: Luca Boccassi <luca.boccassi@microsoft.com>
Link: https://lore.kernel.org/r/20201113211918.71883-2-ebiggers@kernel.org


Signed-off-by: Eric Biggers <ebiggers@google.com>