PCI: mvebu: Use max_t() instead of max(resource_size_t,)

Use max_t() instead of max(resource_size_t,) in order to fix
the following checkpatch warning.

  WARNING: max() should probably be max_t(resource_size_t, SZ_64K, size)
  WARNING: max() should probably be max_t(resource_size_t, SZ_1M, size)

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>