This fixes the following security problems:
* In earlier versions of wolfSSL there exists a potential man in the
middle attack on TLS 1.3 clients.
* Denial of service attack on TLS 1.3 servers from repetitively sending
ChangeCipherSpecs messages. (CVE-2020-12457)
* Potential cache timing attacks on public key operations in builds that
are not using SP (single precision). (CVE-2020-15309)
* When using SGX with EC scalar multiplication the possibility of side-
channel attacks are present.
* Leak of private key in the case that PEM format private keys are
bundled in with PEM certificates into a single file.
* During the handshake, clear application_data messages in epoch 0 are
processed and returned to the application.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>