Change interrupt description from driver name to tty name
(e.g. ttyAML0). If multiple serial ports are enabled this
allows to determine which interrupt belongs to which port
in /proc/interrupts.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>