soc/intel/skylake: Clean up code by using common System Agent module

This patch currently contains the SA initialization
required for bootblock phase -
1. Use SOC_INTEL_COMMON_BLOCK_SA kconfig for common SA code.
2. Perform PCIEXBAR programming based on soc configurable
PCIEX_LENGTH_xxxMB
3. Use common systemagent header file.

Change-Id: I0fa0a60f680b9b00b7f26f1875c553612b123a8e
Signed-off-by: Barnali Sarkar <barnali.sarkar@intel.com>
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/18566
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/soc/intel/skylake/Kconfig b/src/soc/intel/skylake/Kconfig
index ebdcbe3..0108372 100644
--- a/src/soc/intel/skylake/Kconfig
+++ b/src/soc/intel/skylake/Kconfig
@@ -42,6 +42,7 @@
 	select PCIEXP_COMMON_CLOCK
 	select PCIEXP_CLK_PM
 	select PCIEXP_L1_SUB_STATE
+	select PCIEX_LENGTH_64MB
 	select REG_SCRIPT
 	select RELOCATABLE_MODULES
 	select RELOCATABLE_RAMSTAGE
@@ -49,6 +50,7 @@
 	select SOC_INTEL_COMMON
 	select SOC_INTEL_COMMON_ACPI_WAKE_SOURCE
 	select SOC_INTEL_COMMON_BLOCK
+	select SOC_INTEL_COMMON_BLOCK_SA
 	select SOC_INTEL_COMMON_BLOCK_XHCI
 	select SOC_INTEL_COMMON_LPSS_I2C
 	select SOC_INTEL_COMMON_NHLT
@@ -147,10 +149,6 @@
 	hex
 	default 0x400000
 
-config MMCONF_BASE_ADDRESS
-	hex "MMIO Base Address"
-	default 0xe0000000
-
 config MONOTONIC_TIMER_MSR
 	def_bool y
 	select HAVE_MONOTONIC_TIMER