ostree/summary: Eliminate redundant gotos from error handling path
ostree/summary: Eliminate redundant gotos from error handling path

There is no error handling to do, so just return everywhere instead.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Closes: #1158
Approved by: cgwalters

GNOME/ostree,GNOME/ostree,GNOME/ostree,GNOME/ostree,GNOME/ostree