sandbox: i2c: Rename driver names to work with of-platdata

Some of these do not follow the rules. Make sure the driver name matches
the compatible string in all cases.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/rtc/i2c_rtc_emul.c b/drivers/rtc/i2c_rtc_emul.c
index f25b976..fdc885c 100644
--- a/drivers/rtc/i2c_rtc_emul.c
+++ b/drivers/rtc/i2c_rtc_emul.c
@@ -223,7 +223,7 @@
 }
 
 static const struct udevice_id sandbox_i2c_rtc_ids[] = {
-	{ .compatible = "sandbox,i2c-rtc" },
+	{ .compatible = "sandbox,i2c-rtc-emul" },
 	{ }
 };