PCI: dw-rockchip: Add error messages in .probe() error paths

PCI: dw-rockchip: Add error messages in .probe() error paths

Drivers that silently fail to probe provide a bad user experience and
make it unnecessarily hard to debug such a failure.

Fix it by using dev_err_probe() instead of a plain return.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20240227141256.413055-2-ukleinek@debian.org
Signed-off-by: Uwe Kleine-König <ukleinek@debian.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Jesper Nilsson <jesper.nilsson@axis.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>