x86/intel/quark: Fix ptr_ret.cocci warnings

arch/x86/platform/intel-quark/imr.c:280:1-3: WARNING: PTR_ERR_OR_ZERO can be used

 Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Andy Shevchenko <andy.schevchenko@gmail.com>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: kbuild-all@01.org
Link: http://lkml.kernel.org/r/20150219081432.GA21983@waimeaSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/platform/intel-quark/imr.c

@@ -277,10 +277,7 @@ static int imr_debugfs_register(struct imr_device *idev)
 {
 	idev->file = debugfs_create_file("imr_state", S_IFREG | S_IRUGO, NULL,
 					 idev, &imr_state_ops);
-	if (IS_ERR(idev->file))
-		return PTR_ERR(idev->file);
-
-	return 0;
+	return PTR_ERR_OR_ZERO(idev->file);
 }
 
 /**