MINOR: server: move the use_ssl field out of the ifdef USE_OPENSSL

Having it in the ifdef complicates certain operations which require
additional ifdefs just to access a member which could remain zero in
non-ssl cases. Let's move it out, it will not even increase the
struct size on 64-bit machines due to alignment.
diff --git a/include/types/server.h b/include/types/server.h
index 20c314b..5092eb7 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -249,8 +249,8 @@
 	struct sockaddr_storage init_addr;	/* plain IP address specified on the init-addr line */
 	unsigned int init_addr_methods;		/* initial address setting, 3-bit per method, ends at 0, enough to store 10 entries */
 
+	int use_ssl;				/* ssl enabled  */
 #ifdef USE_OPENSSL
-	int use_ssl;				/* ssl enabled */
 	struct {
 		SSL_CTX *ctx;
 		SSL_SESSION *reused_sess;