MINOR: ssl: initialize the sni_keytypes_map as EB_ROOT

The sni_keytypes_map was initialized to {0}, it's better to initialize
it explicitly to EB_ROOT
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 9f6d2b6..2256385 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -3178,7 +3178,7 @@
 {
 	int i = 0, n = 0;
 	struct cert_key_and_chain *certs_and_keys;
-	struct eb_root sni_keytypes_map = { {0} };
+	struct eb_root sni_keytypes_map = EB_ROOT;
 	struct ebmb_node *node;
 	struct ebmb_node *next;
 	/* Array of SSL_CTX pointers corresponding to each possible combo