PCI: endpoint: Do not mark the BAR succeeding a 64-bit BAR as BAR_RESERVED

PCI: endpoint: Do not mark the BAR succeeding a 64-bit BAR as BAR_RESERVED

A BAR that can only be configured as a 64-bit BAR by an EPC driver is
marked as such using the "only_64bit" flag.

Currently, the documentation says that an EPC driver should explicitly
mark the BAR succeeding an "only_64bit" BAR as BAR_RESERVED.

However, a 64-bit BAR will always take up two BARs. It is thus redundant
to mark both BARs.

pci_epc_get_next_free_bar() already skips the BAR succeeding a "only_64bit"
BAR, regardless if the succeeding BAR is marked as BAR_RESERVED or not.

Thus, drop the BAR_RESERVED for a BAR succeeding a "only_64bit" BAR.
No functional changes.

Suggested-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20260312130229.2282001-13-cassel@kernel.org