PCI: mvebu: Do not modify PCI IO type bits in conf_write

PCI: mvebu: Do not modify PCI IO type bits in conf_write

PCI IO type bits are already initialized in mvebu_pci_bridge_emul_init()
function and only when IO support is enabled. These type bits are read-only
and pci-bridge-emul.c code already does not allow to modify them from upper
layers.

When IO support is disabled then all IO registers should be read-only and
return zeros. Therefore do not modify PCI IO type bits in
mvebu_pci_bridge_emul_base_conf_write() callback.

Link: https://lore.kernel.org/r/20211125124605.25915-8-pali@kernel.org
Fixes: 1f08673eef12 ("PCI: mvebu: Convert to PCI emulated bridge config space")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>