staging: android: fix a possible memory leak

Memory allocated by kstrdup should be freed.

CC: Brian Swetland <swetland@google.com>
Acked-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>