commonlib/region: Turn addrspace_32bit into a more official API

We had the addrspace_32bit rdev in prog_loaders.c for a while to help
represent memory ranges as an rdev, and we've found it useful for a
couple of things that have nothing to do with program loading. This
patch moves the concept straight into commonlib/region.c so it is no
longer anchored in such a weird place, and easier to use in unit tests.
Also expand the concept to the whole address space (there's no real need
to restrict it to 32 bits in 64-bit environments) and introduce an
rdev_chain_mem() helper function to make it a bit easier to use. Replace
some direct uses of struct mem_region_device with this new API where it
seems to make sense.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Ie4c763b77f77d227768556a9528681d771a08dca
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52533
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
diff --git a/src/drivers/vpd/vpd.c b/src/drivers/vpd/vpd.c
index d3ff370..a099b3b 100644
--- a/src/drivers/vpd/vpd.c
+++ b/src/drivers/vpd/vpd.c
@@ -101,10 +101,8 @@
 	if (!cbmem)
 		return -1;
 
-	rdev_chain(&ro_vpd, &addrspace_32bit.rdev,
-		   (uintptr_t)cbmem->blob, cbmem->ro_size);
-	rdev_chain(&rw_vpd, &addrspace_32bit.rdev,
-		   (uintptr_t)cbmem->blob + cbmem->ro_size, cbmem->rw_size);
+	rdev_chain_mem(&ro_vpd, cbmem->blob, cbmem->ro_size);
+	rdev_chain_mem(&rw_vpd, cbmem->blob + cbmem->ro_size, cbmem->rw_size);
 
 	return 0;
 }