dm-verity: remove log message with shash driver name

dm-verity: remove log message with shash driver name

I added this log message in commit bbf6a566920e ("dm verity: log the
hash algorithm implementation"), to help people debug issues where they
forgot to enable the architecture-optimized SHA-256 code in their
kconfig or accidentally enabled a slow hardware offload driver (such as
QCE) that overrode the faster CPU-accelerated code.  However:

- The crypto layer now always enables the architecture-optimized SHA-1,
  SHA-256, and SHA-512 code.  Moreover, for simplicity the driver name
  is now fixed at "sha1-lib", "sha256-lib", etc.

- dm-verity now uses crypto_shash instead of crypto_ahash, preventing
  the mistake of accidentally using a slow driver such as QCE.

Therefore, this log message generally no longer provides useful
information.  Remove it.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>