drm: Remove DRM_ERR OS macro.

This was used to make all ioctl handlers return -errno on linux and errno on
*BSD.  Instead, just return -errno in shared code, and flip sign on return f
shared code to *BSD code.

Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/drm_lock.c b/drivers/char/drm/drm_lock.c
index c0534b5..950e78d 100644
--- a/drivers/char/drm/drm_lock.c
+++ b/drivers/char/drm/drm_lock.c
@@ -125,7 +125,7 @@
 	if (dev->driver->dma_quiescent && (lock.flags & _DRM_LOCK_QUIESCENT)) {
 		if (dev->driver->dma_quiescent(dev)) {
 			DRM_DEBUG("%d waiting for DMA quiescent\n", lock.context);
-			return DRM_ERR(EBUSY);
+			return -EBUSY;
 		}
 	}