usb_try_create_simple() is qdev_try_new() and qdev_realize_and_unref()
with more verbose error messages. Of its two users, one ignores
errors, and the other asserts they are impossible.
Make them use qdev_try_new() and qdev_realize_and_unref() directly,
and eliminate usb_try_create_simple
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-30-armbru@redhat.com>