libnetconf2 UPDATE merge SSH and TLS req into one

In this commit I made the changes that if you want to use TLS, you have
to have both OpenSSL and libssh installed and viceversa. Set the minimum
required OpenSSL version to 3.0 and 0.9.5 for libssh.
diff --git a/src/session_server_ch.h b/src/session_server_ch.h
index bf59ce4..76b6adf 100644
--- a/src/session_server_ch.h
+++ b/src/session_server_ch.h
@@ -27,7 +27,7 @@
 #include "netconf.h"
 #include "session.h"
 
-#if defined (NC_ENABLED_SSH) || defined (NC_ENABLED_TLS)
+#ifdef NC_ENABLED_SSH_TLS
 
 /**
  * @defgroup server_ch Server-side Call Home
@@ -234,10 +234,6 @@
 
 /** @} Server-side Call Home */
 
-#endif /* NC_ENABLED_SSH || NC_ENABLED_TLS */
-
-#ifdef NC_ENABLED_SSH
-
 /**
  * @defgroup server_ch_ssh Server-side Call Home on SSH
  * @ingroup server_ch
@@ -323,10 +319,6 @@
 
 /** @} Server-side Call Home on SSH */
 
-#endif /* NC_ENABLED_SSH */
-
-#ifdef NC_ENABLED_TLS
-
 /**
  * @defgroup server_ch_tls Server-side Call Home on TLS
  * @ingroup server_ch
@@ -457,7 +449,7 @@
 
 /** @} Server-side Call Home on TLS */
 
-#endif /* NC_ENABLED_TLS */
+#endif /* NC_ENABLED_SSH_TLS */
 
 #ifdef __cplusplus
 }