PCI: Add a generic weak pcibios_align_resource()

Multiple architectures define this as a trivial function, and I'm adding
another one as part of the RISC-V port.  Add a __weak version of
pcibios_align_resource() and delete the now-obselete ones in a handful of
ports.

The only functional change should be that a handful of ports used to export
pcibios_fixup_bus().  Only some architectures export this, so I just
dropped it.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

arch/arm64/kernel/pci.c

@@ -22,15 +22,6 @@
 #include <linux/pci-ecam.h>
 #include <linux/slab.h>
 
-/*
- * We don't have to worry about legacy ISA devices, so nothing to do here
- */
-resource_size_t pcibios_align_resource(void *data, const struct resource *res,
-				resource_size_t size, resource_size_t align)
-{
-	return res->start;
-}
-
 #ifdef CONFIG_ACPI
 /*
  * Try to assign the IRQ number when probing a new device