reset: implement a reset test

This adds a sandbox reset implementation (provider), a test client
device, instantiates them both from Sandbox's DT, and adds a DM test
that excercises everything.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 686c215..879b30e 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -259,6 +259,17 @@
 		compatible = "sandbox,reset";
 	};
 
+	resetc: reset-ctl {
+		compatible = "sandbox,reset-ctl";
+		#reset-cells = <1>;
+	};
+
+	reset-ctl-test {
+		compatible = "sandbox,reset-ctl-test";
+		resets = <&resetc 100>, <&resetc 2>;
+		reset-names = "other", "test";
+	};
+
 	rproc_1: rproc@1 {
 		compatible = "sandbox,test-processor";
 		remoteproc-name = "remoteproc-test-dev1";