reset: Add reset valid

Add reset_valid to check whether given reset is valid
or not.

Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/include/reset.h b/include/reset.h
index bc495a9..65aa7a4 100644
--- a/include/reset.h
+++ b/include/reset.h
@@ -306,4 +306,15 @@
 }
 #endif
 
+/**
+ * reset_valid() - check if reset is valid
+ *
+ * @reset_ctl:		the reset to check
+ * @return TRUE if valid, or FALSE
+ */
+static inline bool reset_valid(struct reset_ctl *reset_ctl)
+{
+	return !!reset_ctl->dev;
+}
+
 #endif