x86/PCI: Mark DMI tables as initialization data

The DMI tables are only used in __init code, thereby can be marked as
initialization data, too.  The same is true for the callback functions
referenced from the DMI tables.

This moves ~9.6 kB of code and r/o data to the init sections, marking the
memory for release after initialization.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>