reset: add reset_request()

This is needed in error path to assert previously deasserted
reset by using a saved reset_ctl reference.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/reset.h b/include/reset.h
index f45fcf8..4f2e35f 100644
--- a/include/reset.h
+++ b/include/reset.h
@@ -100,6 +100,15 @@
 		      struct reset_ctl *reset_ctl);
 
 /**
+ * reset_request - Request a reset signal.
+ *
+ * @reset_ctl:	A reset control struct.
+ *
+ * @return 0 if OK, or a negative error code.
+ */
+int reset_request(struct reset_ctl *reset_ctl);
+
+/**
  * reset_free - Free a previously requested reset signal.
  *
  * @reset_ctl:	A reset control struct that was previously successfully