AMD K8 fam10: Refactor Kconfig SB_HT_CHAIN_ON_BUS0

If SB_HT_CHAIN_ON_BUS0 is selected, HyperTransport chain for System Bus
is the first to scan and it will be assigned with bus number 0.

If HT_CHAIN_DISTRIBUTE is selected, each link will reserve a fixed range
of bus numbers instead of assigning consecutive numbers across all the links.

All fam10 have SB_HT_CHAIN_ON_BUS0 selected under northbridge.
Follow-up can easily drop this if we find this is dictated by architecture.

Change-Id: I8deddcb4c3fd679b6b27e2879d9dba3895c4dd6f
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/8366
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>
Reviewed-by: Timothy Pearson <tpearson@raptorengineeringinc.com>

src/mainboard/gigabyte/ga_2761gxdk/Kconfig

@@ -6,6 +6,7 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	select DIMM_DDR2
 	select NORTHBRIDGE_AMD_AMDK8
 	select SOUTHBRIDGE_SIS_SIS966
+	select HT_CHAIN_DISTRIBUTE
 	select SUPERIO_ITE_IT8716F
 	select PARALLEL_CPU_INIT
 	select HAVE_OPTION_TABLE
@@ -37,10 +38,6 @@ config MEM_TRAIN_SEQ
 	int
 	default 2
 
-config SB_HT_CHAIN_ON_BUS0
-	int
-	default 2
-
 config MAINBOARD_PART_NUMBER
 	string
 	default "GA-2761GXDK"

src/mainboard/gigabyte/m57sli/Kconfig

@@ -6,6 +6,7 @@ config BOARD_SPECIFIC_OPTIONS # dummy
 	select DIMM_DDR2
 	select NORTHBRIDGE_AMD_AMDK8
 	select SOUTHBRIDGE_NVIDIA_MCP55
+	select HT_CHAIN_DISTRIBUTE
 	select MCP55_USE_NIC
 	select MCP55_USE_AZA
 	select SUPERIO_ITE_IT8716F
@@ -41,10 +42,6 @@ config MEM_TRAIN_SEQ
 	int
 	default 2
 
-config SB_HT_CHAIN_ON_BUS0
-	int
-	default 2
-
 config MAINBOARD_PART_NUMBER
 	string
 	default "GA-M57SLI-S4"

src/mainboard/gigabyte/ma785gm/Kconfig

@@ -40,10 +40,6 @@ config MAX_PHYSICAL_CPUS
 	int
 	default 2
 
-config SB_HT_CHAIN_ON_BUS0
-	int
-	default 1
-
 config HT_CHAIN_END_UNITID_BASE
 	hex
 	default 0x1

src/mainboard/gigabyte/ma785gmt/Kconfig

@@ -40,10 +40,6 @@ config MAX_PHYSICAL_CPUS
 	int
 	default 2
 
-config SB_HT_CHAIN_ON_BUS0
-	int
-	default 1
-
 config HT_CHAIN_END_UNITID_BASE
 	hex
 	default 0x1

src/mainboard/gigabyte/ma78gm/Kconfig

@@ -40,10 +40,6 @@ config MAX_PHYSICAL_CPUS
 	int
 	default 2
 
-config SB_HT_CHAIN_ON_BUS0
-	int
-	default 1
-
 config HT_CHAIN_END_UNITID_BASE
 	hex
 	default 0x1