resource: Increase MAX_IORES_LEVEL to 8

resource: Increase MAX_IORES_LEVEL to 8

While debugging a PCI resource allocation issue, the resources for many
nested bridges and endpoints got flattened in /proc/iomem by
MAX_IORES_LEVEL that is set to 5. This made the iomem output hard to
read as the visual hierarchy cues were lost.

Increase MAX_IORES_LEVEL to 8 to avoid flattening PCI topologies with
nested bridges so aggressively (the case in the Link has the deepest
resource at level 7 so 8 looks a reasonable limit).

Link: https://bugzilla.kernel.org/show_bug.cgi?id=220775
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20251219174036.16738-5-ilpo.jarvinen@linux.intel.com