dm: sf: Add support for all targets which requires MANUAL_RELOC

dm: sf: Add support for all targets which requires MANUAL_RELOC

It is follow up patch based on
"dm: Add support for all targets which requires MANUAL_RELOC"
(sha1: 484fdf5ba058b07be5ca82763aa2b72063540ef3)
to update function pointers for DM.

Using post_bind is not ideal but it is one on current option what can be
used. Variable reloc_done has to be used do not call relocation after
every bind. Maybe new core functions should be introduced for this case.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>