PCI: keystone: Describe Resizable BARs as Resizable BARs

PCI: keystone: Describe Resizable BARs as Resizable BARs

Looking at section "12.2.2.4.15 PCIe Subsystem BAR Configuration" in the
following Technical Reference Manual (TRM) for AM65x:

  https://www.ti.com/lit/ug/spruid7e/spruid7e.pdf

We can see that BAR2 and BAR5 are not Fixed BARs, but actually Resizable
BARs.

Now when we actually have support for Resizable BARs, let's configure
these BARs as such.

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20250131182949.465530-14-cassel@kernel.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>