PCI: dwc: ep: Rename dw_pcie_ep_init_complete() to dw_pcie_ep_init_registers()

The goal of the dw_pcie_ep_init_complete() API is to initialize the DWC
specific registers post registering the controller with the EP framework.

But the naming doesn't reflect its functionality and causes confusion. So,
let's rename it to dw_pcie_ep_init_registers() to make it clear that it
initializes the DWC specific registers.

Link: https://lore.kernel.org/linux-pci/20240327-pci-dbi-rework-v12-6-082625472414@linaro.org


Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>