device (rather, the device that carries that attribute) also
carry one or more attributes indicating which type of controller
it might be.
This will allow systems that might have AGP, but would never have
e.g. an Intel PCI-Host bridge, to trim out code that won't be used.
-allocate space for DMA segments as much as necessary
-fix format warnings in a debug output
-don't try to access AGP capability stuff in the PCI config header
if it doesn't exist (as on the i810)
fvdl