drm: xylon: irq: replace DRM_WAKEUP() with wake_up()

DRM_WAKEUP() has been removed, so replace DRM_WAKEUP() call with wake_up().

Signed-off-by: Hyun Kwon <hyunk@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>