xen-blkfront: don't add indirect pages to list when !feature_persistent
xen-blkfront: don't add indirect pages to list when !feature_persistent

We should consider info->feature_persistent when adding indirect page to list
info->indirect_pages, else the BUG_ON() in blkif_free() would be triggered.

When we are using persistent grants the indirect_pages list
should always be empty because blkfront has pre-allocated enough
persistent pages to fill all requests on the ring.

CC: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org
Acked-by: Roger Pau Monné <1c35b25b17252e1e5021df00666589fc74f64580@citrix.com>
Signed-off-by: Bob Liu <f1431bf4ea962ea2009f7275289c2e0b23d8aceb@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <da3a51b335cef0eb0e2c329c5ef6bcd6acef687a@oracle.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs