lib/prog_loaders, soc/amd/: Make payload_preload use cbfs_preload

Now that CBFS has this functionality built in, we no longer need to
manually code it.

payload_preload used to use the payload_preload_cache region to store
the raw payload contents. This region was placed outside the firmware
reserved region, so it was available for use by the OS. This was
possible because the payload isn't loaded again on S3 resume.

cbfs_preload only uses the cbfs_cache region. This region must be
reserved because it gets used on the S3 resume path. Unfortunately this
means that cbfs_cache must be increased to hold the payload. Cezanne is
the only platform currently using payload_preload, and the size of
cbfs_cache has already been adjusted.

In the future we could look into adding an option to cbfs_preload that
would allow it to use a different memory pool for the cache allocation.

BUG=b:179699789
TEST=Boot guybrush and verify preloading the payload was successful
CBFS DEBUG: get_preload_rdev(name='fallback/payload') preload successful

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: Idc521b238620ff52b8ba481cd3c10e5c4f1394bd
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58962
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>

src/lib/Kconfig

@@ -114,14 +114,3 @@ config CBFS_PRELOAD
 	  in the background before they are actually required. This feature
 	  depends on the read-only boot_device having a DMA controller to
 	  perform the background transfer.
-
-config PAYLOAD_PRELOAD
-	bool
-	depends on COOP_MULTITASKING
-	help
-	  On some systems with SPI DMA controllers, it is possible to preload
-	  the payload while ramstage is executing. This can be selected by the
-	  SoC to enable payload preloading.
-
-	  The SoC needs to define a payload_preload_cache region where the
-	  raw payload can be placed.