sandbox: Use the reset driver to handle reset

Move sandbox over to use the reset uclass for reset, instead of a direct
call to do_reset(). This allows us to add tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/cpu/cpu.c b/arch/sandbox/cpu/cpu.c
index e6ddb17..3a7f5a0 100644
--- a/arch/sandbox/cpu/cpu.c
+++ b/arch/sandbox/cpu/cpu.c
@@ -20,7 +20,7 @@
 unsigned long map_len;
 #endif
 
-void reset_cpu(ulong ignored)
+void sandbox_exit(void)
 {
 	/* Do this here while it still has an effect */
 	os_fd_restore();
@@ -34,13 +34,6 @@
 	os_exit(0);
 }
 
-int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
-{
-	reset_cpu(0);
-
-	return 0;
-}
-
 /* delay x useconds */
 void __udelay(unsigned long usec)
 {
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 3c9abb3..79b0175 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -196,6 +196,14 @@
 		};
 	};
 
+	reset@0 {
+		compatible = "sandbox,warm-reset";
+	};
+
+	reset@1 {
+		compatible = "sandbox,reset";
+	};
+
 	spi@0 {
 		#address-cells = <1>;
 		#size-cells = <0>;
diff --git a/arch/sandbox/include/asm/u-boot-sandbox.h b/arch/sandbox/include/asm/u-boot-sandbox.h
index da87cc3..2f3c3f9 100644
--- a/arch/sandbox/include/asm/u-boot-sandbox.h
+++ b/arch/sandbox/include/asm/u-boot-sandbox.h
@@ -83,4 +83,7 @@
  */
 int sandbox_read_fdt_from_file(void);
 
+/* Exit sandbox (quit U-Boot) */
+void sandbox_exit(void);
+
 #endif	/* _U_BOOT_SANDBOX_H_ */