nat: When having a proper close down, or a short read close the connection

For now close the connection when having a short read. This might
be due a network issue (loss of segment) or similiar. As we are not
handling these issues well, let us close the connection.
diff --git a/openbsc/src/nat/bsc_nat.c b/openbsc/src/nat/bsc_nat.c
index 6b29d16..d5ed751 100644
--- a/openbsc/src/nat/bsc_nat.c
+++ b/openbsc/src/nat/bsc_nat.c
@@ -383,13 +383,12 @@
 	struct ipaccess_head *hh;
 
 	if (!msg) {
-		if (error == 0) {
+		if (error == 0)
 			LOGP(DNAT, LOGL_FATAL, "The connection the MSC was lost, exiting\n");
-			bsc_msc_lost(msc_con);
-			return -1;
-		}
+		else
+			LOGP(DNAT, LOGL_ERROR, "Failed to parse ip access message: %d\n", error);
 
-		LOGP(DNAT, LOGL_ERROR, "Failed to parse ip access message: %d\n", error);
+		bsc_msc_lost(msc_con);
 		return -1;
 	}
 
@@ -600,12 +599,12 @@
 	struct msgb *msg = ipaccess_read_msg(bfd, &error);
 
 	if (!msg) {
-		if (error == 0) {
+		if (error == 0)
 			LOGP(DNAT, LOGL_ERROR,	"The connection to the BSC was lost. Cleaning it\n");
-			remove_bsc_connection(bsc);
-		} else {
+		else
 			LOGP(DNAT, LOGL_ERROR, "Failed to parse ip access message: %d\n", error);
-		}
+
+		remove_bsc_connection(bsc);
 		return -1;
 	}