Staging: dream: fix memory leak in camera error path

cppcheck found that ctrl_pmsm is leaked if the open operation fails.

Signed-off-by: Eric Sesterhenn <eric.sesterhenn@lsexperts.de>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>