PCI: tegra: Add SW fixup for RAW violations

The logic which blocks read requests till AFI gets ACK for all outstanding
writes from memory controller does not behave correctly when number of
outstanding writes become more than 32 in Tegra124 and Tegra132.

SW fixup is to prevent writes from accumulating more than 32 by:

- limiting outstanding posted writes to 14
- modifying Gen1 and Gen2 UpdateFC timer frequency

UpdateFC timer frequency is equal to twice the value of register content
in nsec. These settings are recommended after stress testing with
different values.

Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Thierry Reding <treding@nvidia.com>