PCI: xilinx-nwl: Remove redundant code that sets Type 1 header fields

The PCI core already updates the primary, secondary and subordinate bus
number registers fields of the Type 1 header.

Thus, remove the redundant code from the nwl_pcie_bridge_init().

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20231016051102.1180432-2-thippeswamy.havalige@amd.com


Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>