hw/xen: Add "mode" parameter to xen-block devices

Block devices don't work in PV Grub (0.9x) if there is no mode specified. It
complains: "Error ENOENT when reading the mode"

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20250207143724.30792-2-dwmw2@infradead.org>
Signed-off-by: Anthony PERARD <anthony.perard@vates.tech>
1 file changed