protocol: Add get_info

Change-Id: Ie3338714813bb65f5d37fcd046dd5bebc0ba21f0
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/lpc.c b/lpc.c
index 2c8b00d..4b9d384 100644
--- a/lpc.c
+++ b/lpc.c
@@ -170,7 +170,7 @@
 		  &map)) {
 		MSG_ERR("Failed to point the LPC BUS to memory: %s\n",
 			strerror(errno));
-		return -MBOX_R_SYSTEM_ERROR;
+		return -errno;
 	}
 
 	/* LPC now maps memory (keep suspended state) */