ARM: cleanup: OMAP hwmod error checking

omap_hwmod_lookup() only returns NULL on error, never an error pointer.
Checking the returned pointer using IS_ERR_OR_NULL() is needless
overhead.  Use a simple !ptr check instead.

OMAP devices (oh->od) always have a valid platform device attached (see
omap_device_alloc()) so there's no point validating the platform device
pointer (we will have already oopsed long before if this is not the
case here.)

Lastly, oh->od is only ever NULL or a valid omap device pointer - 'oh'
comes from the statically declared hwmod tables, and the pointer is
only filled in by omap_device_alloc() at a point where the omap device
pointer must be valid.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-omap2/omap_device.c

@@ -1157,20 +1157,17 @@ struct device *omap_device_get_by_hwmod_name(const char *oh_name)
 	}
 
 	oh = omap_hwmod_lookup(oh_name);
-	if (IS_ERR_OR_NULL(oh)) {
+	if (!oh) {
 		WARN(1, "%s: no hwmod for %s\n", __func__,
 			oh_name);
-		return ERR_PTR(oh ? PTR_ERR(oh) : -ENODEV);
+		return -ENODEV;
 	}
-	if (IS_ERR_OR_NULL(oh->od)) {
+	if (!oh->od) {
 		WARN(1, "%s: no omap_device for %s\n", __func__,
 			oh_name);
-		return ERR_PTR(oh->od ? PTR_ERR(oh->od) : -ENODEV);
+		return -ENODEV;
 	}
 
-	if (IS_ERR_OR_NULL(oh->od->pdev))
-		return ERR_PTR(oh->od->pdev ? PTR_ERR(oh->od->pdev) : -ENODEV);
-
 	return &oh->od->pdev->dev;
 }
 EXPORT_SYMBOL(omap_device_get_by_hwmod_name);