x86/pci: Remove OLPC dead code

3ef0e1f8 ("x86: olpc: add One Laptop Per Child architecture support")
added a commented-out EHCI config section that has never been used.

Remove this dead code.

Link: https://lore.kernel.org/r/20240125030623.513902-1-chentao@kylinos.cn


Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>