disp:msm: fix return type from runtime api

pm_runtime_get_sync api can return non-zero return value
for success case. For such cases the IOCTL should return
success.

Change-Id: I5868cfc3c0cdeb63c3b2e68f1dcddadcd0aae9ce
Signed-off-by: Abhijit Kulkarni <[email protected]>

msm/msm_drv.c

@@ -1593,6 +1593,8 @@ int msm_ioctl_power_ctrl(struct drm_device *dev, void *data,
 
 		if (rc < 0)
 			ctx->enable_refcnt = old_cnt;
+		else
+			rc = 0;
 	}
 
 	pr_debug("pid %d enable %d, refcnt %d, vote_req %d\n",