PCI: rockchip: Add poll and timeout to wait for PHY PLLs to be locked

PCI: rockchip: Add poll and timeout to wait for PHY PLLs to be locked

The RK3399 PCIe controller should wait until the PHY PLLs are locked.
Add poll and timeout to wait for PHY PLLs to be locked. If they cannot
be locked generate error message and jump to error handler. Accessing
registers in the PHY clock domain when PLLs are not locked causes hang
The PHY PLLs status is checked through a side channel register.
This is documented in the TRM section 17.5.8.1 "PCIe Initialization
Sequence".

Link: https://lore.kernel.org/r/20230418074700.1083505-5-rick.wertenbroek@gmail.com
Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller")
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Rick Wertenbroek <rick.wertenbroek@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Cc: stable@vger.kernel.org