serial: imx: ignore framing errors when IGNPAR is set.

When IGNPAR is set in termios->c_iflag,  characters with
framing errors should be ignored.

Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>