soc/amd/cezanne,common,picasso: use BERT region reserved by FSP driver

commit ce0e2a0140 (drivers/intel/fsp2_0:
use FSP to allocate APEI BERT memory region) adds a mechanism to reserve
the BERT region inside the coreboot code, so we can get rid of the
workaround to reserve it in the FSP and return the location in a HOB.
mcfg->bert_size defaults to 0 which makes the FSP not generate the
corresponding HOB, but that field is planned to be removed at least on
Cezanne, so don't explicitly set it to 0.

BUG=b:169934025
TEST=BERT table that gets generated in a follow-up patch for Picasso
points to expected BERT region and Linux is able to access, decode and
display it.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: Iaca89b47793bf9982181560f026459a18e7db134
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52584
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/picasso/fsp_m_params.c

@@ -68,7 +68,6 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 
 	mcfg->pci_express_base_addr = CONFIG_MMCONF_BASE_ADDRESS;
 	mcfg->tseg_size = CONFIG_SMM_TSEG_SIZE;
-	mcfg->bert_size = CONFIG_ACPI_BERT_SIZE;
 	mcfg->serial_port_base = uart_platform_base(CONFIG_UART_FOR_CONSOLE);
 	mcfg->serial_port_use_mmio = CONFIG(DRIVERS_UART_8250MEM);
 	mcfg->serial_port_stride = CONFIG(DRIVERS_UART_8250MEM_32) ? 4 : 1;