AGESA SPI: Fix Kconfig options

Option AMD_SB_SPI_LEN leaked to non-AMD configs.
Option SPI_FLASH is compulsory with HAVE_ACPI_RESUME.

Change-Id: Ib84c4d9e4fdf670b32b0cae7280fcbb6d3aecaf5
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5606
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-by: Idwer Vollering <vidwer@gmail.com>

src/cpu/amd/agesa/Kconfig

@@ -29,6 +29,7 @@ config CPU_AMD_AGESA
 	select TSC_SYNC_LFENCE
 	select UDELAY_LAPIC
 	select LAPIC_MONOTONIC_TIMER
+	select SPI_FLASH if HAVE_ACPI_RESUME
 
 if CPU_AMD_AGESA
 

src/southbridge/amd/Kconfig

@@ -15,9 +15,11 @@ source src/southbridge/amd/cimx/Kconfig
 source src/southbridge/amd/agesa/Kconfig
 source src/southbridge/amd/sr5650/Kconfig
 
-config SPI_FLASH
-	bool
-	default y if HAVE_ACPI_RESUME && CPU_AMD_AGESA
+if CPU_AMD_AGESA
+
 config AMD_SB_SPI_TX_LEN
 	int
 	default 4
+	depends on SPI_FLASH
+
+endif

src/southbridge/amd/agesa/hudson/Kconfig

@@ -243,6 +243,7 @@ if SOUTHBRIDGE_AMD_AGESA_YANGTZE
 	config AMD_SB_SPI_TX_LEN
 		int
 		default 64
+		depends on SPI_FLASH
 
 	config AZ_PIN
 		hex