RK3588 PCIe Bifurcation Fixes

Michal Tomek reported PCIe bifurcation issues with CM3588. He already debugged them and provided some patches. I've investigated and completed them and added them to the rk3588-test branch. They are mostly ready to be send upstream.

assigned to @sre

changed title from Fix PCIe bifurcation to RK3588 Fix PCIe bifurcation

changed title from RK3588 Fix PCIe bifurcation to RK3588 PCIe Bifurcation Fixes

Michal Tomek confirmed, that the patches are working for him with phy1 uninitialized and phy2 in USB3 mode on CM3588.

added T49419 label

While checking the PCIe bifurcation bits, I found one more issue and fixed it up.

https://lore.kernel.org/all/171239513079.352254.15391125336022363426.b4-ty@kernel.org/

closed

mentioned in commit cristicc/linux-next@d659b715

mentioned in commit 1c7b17cf