dm: systemace: Drop the get_dev() function

This function is implemented by the legacy block functions now. Drop it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/disk/part.c b/disk/part.c
index 4fc774b..28c8706 100644
--- a/disk/part.c
+++ b/disk/part.c
@@ -41,7 +41,7 @@
 	},
 #endif
 #if defined(CONFIG_SYSTEMACE)
-	{ .name = "ace", .get_dev = systemace_get_dev, },
+	{ .name = "ace", },
 #endif
 #if defined(CONFIG_SANDBOX)
 	{ .name = "host", .get_dev = host_get_dev, },