SSH connection status indicators

- Add Connected bool field to vfs.Entry and RemoteMount
- Track connection status in sshState.connectedHosts
- Show status icon (connected/disconnected) in pane header when browsing remote host
- Async SSH connection test with cancel support for Add Host dialog
- Colored labels and styled help text in SSH dialogs
- Confirmation dialog when deleting manually-added SSH hosts

vendor/golang.org/x/sys/unix/syscall_solaris.go

@@ -1052,14 +1052,6 @@ func IoctlSetIntRetInt(fd int, req int, arg int) (int, error) {
 	return ioctlRet(fd, req, uintptr(arg))
 }
 
-func IoctlSetString(fd int, req int, val string) error {
-	bs := make([]byte, len(val)+1)
-	copy(bs[:len(bs)-1], val)
-	err := ioctlPtr(fd, req, unsafe.Pointer(&bs[0]))
-	runtime.KeepAlive(&bs[0])
-	return err
-}
-
 // Lifreq Helpers
 
 func (l *Lifreq) SetName(name string) error {