crypto: qat - make pfvf send message direction agnostic

The functions adf_iov_putmsg() and __adf_iov_putmsg() are shared by both
PF and VF. Any logging or documentation should not refer to any specific
direction.

Make comments and log messages direction agnostic by replacing PF2VF
with PFVF. Also fix the wording for some related comments.

Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>