Revert "PCI: Cache PCIe Device Capabilities register"

This reverts commit 619013d7 which is
commit 69139244 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ic2bd4ea9575eb5c79e0a77f0f65a88f0245c3b4a
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>