Add some missing initialisations.

Spotted by valgrind, after I was testing all the Coverity bug fixes :-)

dialog.c

@@ -381,6 +381,7 @@ union control *ctrl_droplist(struct controlset *s, char *label, char shortcut,
     c->listbox.percentwidth = percentage;
     c->listbox.ncols = 0;
     c->listbox.percentages = NULL;
+    c->listbox.hscroll = FALSE;
     return c;
 }
 
@@ -397,6 +398,7 @@ union control *ctrl_draglist(struct controlset *s,char *label,char shortcut,
     c->listbox.percentwidth = 100;
     c->listbox.ncols = 0;
     c->listbox.percentages = NULL;
+    c->listbox.hscroll = FALSE;
     return c;
 }
 

ssh.c

@@ -10598,6 +10598,8 @@ static const char *ssh_init(void *frontend_handle, void **backend_handle,
     ssh->sent_console_eof = FALSE;
     ssh->got_pty = FALSE;
     ssh->bare_connection = FALSE;
+    ssh->X11_fwd_enabled = FALSE;
+    ssh->connshare = NULL;
     ssh->attempting_connshare = FALSE;
 
     *backend_handle = ssh;