Revert "tty: serial: imx.c: Reset UART before activating interrupts"

This reverts commit e95044ba.

Commit e95044ba ("tty: serial: imx.c: Reset UART before activating
interrupts") terribly messes up with the console on mx6 boards, so
let's revert it.

Reported-by: kernelci.org bot <bot@kernelci.org>
Cc: David Jander <david@protonic.nl>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>