crypto/openssl: rename libcrypto to openssl

crypto/openssl: rename libcrypto to openssl

This patch replaces name "libcrypto" to "openssl" from file directories,
symbol prefixes and sub-names connected with old name.
Renamed poll mode driver files, test files, and documentations.
It is done to better name association with library because
the cryptography operations are using Openssl library crypto API.

Fixes: d61f70b4c918 ("crypto/libcrypto: add driver for OpenSSL library")
Signed-off-by: Slawomir Mrozowicz <slawomirx.mrozowicz@intel.com>
Acked-by: Deepak Kumar Jain <deepak.k.jain@intel.com>