USB: gadget: f_mass_storage::fsg_bind(): fix error handling

Contrary to the comment in fsg_add, fsg_bind calls fsg_unbind on errors,
which decreases refcount and frees the fsg_dev structure, causing trouble
when fsg_add does the same.

Fix it by simply leaving up cleanup to fsg_add().

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index db08de2..f4911c0 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -2954,7 +2954,6 @@
 autoconf_fail:
 	ERROR(fsg, "unable to autoconfigure all endpoints\n");
 	rc = -ENOTSUPP;
-	fsg_unbind(c, f);
 	return rc;
 }