mips: octeon_nic23: Add PCIe FLR fixup via cyclic infrastructure

This patch adds a fixup function related to a PCIe FLR (Function Level
Reset) problem on the NIC23 PCIe board. This function is imported from
the Marvell Octeon 2013 U-Boot version as a (nearly) verbatim copy. It
uses the newly introduced cyclic infrastructure, so that this function
gets called every 100us, which is needed to detect this FLR issue.

Signed-off-by: Aaron Williams <awilliams@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>