ssl.c: Move functions out to own files and add testing

ssl_api_pk.c: added Public-key APIs (min/max key sizes, DH key test,
signature NIDs, tmp ecdh. Reworked code of new functions.
ssl_api_cert.c: added more SSL Certificate APIs. Reworked code of new
functions.
ssl_api_ext.c: TLS extension APIs (session tickets, max fragment,
groups, etc.). Reworked code.
ssl_api_dtls.c: DTLS APIs (cookie secret, etc.)

Improved test coverage for functions moved.

Author: SparkiDev

CMakeLists.txt

@@ -2945,6 +2945,9 @@ if(WOLFSSL_EXAMPLES)
         tests/api/test_lms_xmss.c
         tests/api/test_dtls.c
         tests/api/test_dtls13.c
+        tests/api/test_ssl_cert.c
+        tests/api/test_ssl_pk.c
+        tests/api/test_ssl_ext.c
         tests/api/test_ocsp.c
         tests/api/test_evp.c
         tests/api/test_tls_ext.c

src/include.am

@@ -21,6 +21,8 @@ EXTRA_DIST += src/pk_rsa.c
 EXTRA_DIST += src/pk_ec.c
 EXTRA_DIST += src/ssl_api_cert.c
 EXTRA_DIST += src/ssl_api_crl_ocsp.c
+EXTRA_DIST += src/ssl_api_dtls.c
+EXTRA_DIST += src/ssl_api_ext.c
 EXTRA_DIST += src/ssl_api_pk.c
 EXTRA_DIST += src/ssl_asn1.c
 EXTRA_DIST += src/ssl_bn.c