drm: fix some spelling mistakes

Signed-off-by: NFrank Binns <frank.binns@imgtec.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466763337-27428-1-git-send-email-frank.binns@imgtec.com

drivers/gpu/drm/drm_irq.c

@@ -532,7 +532,7 @@ int drm_irq_uninstall(struct drm_device *dev)
 
 	/*
 	 * Wake up any waiters so they don't hang. This is just to paper over
-	 * isssues for UMS drivers which aren't in full control of their
+	 * issues for UMS drivers which aren't in full control of their
 	 * vblank/irq handling. KMS drivers must ensure that vblanks are all
 	 * disabled when uninstalling the irq handler.
 	 */
@@ -594,7 +594,7 @@ int drm_control(struct drm_device *dev, void *data,
 		return 0;
 	if (drm_core_check_feature(dev, DRIVER_MODESET))
 		return 0;
-	/* UMS was only ever support on pci devices. */
+	/* UMS was only ever supported on pci devices. */
 	if (WARN_ON(!dev->pdev))
 		return -EINVAL;