Add code improvments and refactoring in dealing with ALPN

Signed-off-by: Waleed Elmelegy <waleed.elmelegy@arm.com>
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 948c802..a8807f6 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2855,8 +2855,8 @@
 #if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_EARLY_DATA) && \
     defined(MBEDTLS_SSL_ALPN)
 MBEDTLS_CHECK_RETURN_CRITICAL
-int mbedtls_ssl_session_set_alpn(mbedtls_ssl_session *session,
-                                 const char *alpn);
+int mbedtls_ssl_session_set_ticket_alpn(mbedtls_ssl_session *session,
+                                        const char *alpn);
 #endif
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)