soc,sb/amd: Change SPI controller resource

This replaces IORESOURCE_SUBTRACTIVE with IORESOURCE_RESERVE.

Change-Id: Ib3d934ca704273daacbeb3c52412bf04e2be7217
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64695
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/southbridge/amd/agesa/hudson/lpc.c b/src/southbridge/amd/agesa/hudson/lpc.c
index f6e256b..fd710ab 100644
--- a/src/southbridge/amd/agesa/hudson/lpc.c
+++ b/src/southbridge/amd/agesa/hudson/lpc.c
@@ -95,7 +95,7 @@
 		     IORESOURCE_ASSIGNED | IORESOURCE_FIXED;
 
 	/* Add a memory resource for the SPI BAR. */
-	fixed_mem_resource_kb(dev, 2, SPI_BASE_ADDRESS / 1024, 1, IORESOURCE_SUBTRACTIVE);
+	mmio_range(dev, 2, SPI_BASE_ADDRESS, 1 * KiB);
 
 	res = new_resource(dev, 3); /* IOAPIC */
 	res->base = IO_APIC_ADDR;