genpart: return 0 if partition writen OK, with no do_magic

If do_magic is false, we don't won't write the 0xaa55 magic.
However, if we succesfully wrote the partition entry, we still
want to return 0 to indicate success.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Robert Schwebel <r.schwebel@pengutronix.de>

--
Patch sent upstream, but no mailing list.
Status: accepted upstream, not yet released.

diff -durN host-genpart-1.0.2.orig/src/genpart.c host-genpart-1.0.2/src/genpart.c
--- host-genpart-1.0.2.orig/src/genpart.c	2009-12-20 21:54:56.000000000 +0100
+++ host-genpart-1.0.2/src/genpart.c	2013-01-22 23:13:24.109752579 +0100
@@ -92,6 +92,8 @@
 		if (do_magic) {
 			if (fwrite(&magic, 2, 1, stdout) > 0)
 				rc=0;
+		} else {
+			rc=0;
 		}
 	}
 	return rc;