x86: Support reset routines in bootblock

Expand the boot block include file to allow for a file containing reset
routines to be added.  Prevent breaking existing platforms by using a
Kconfig value to specify the path to this file, and have the code
include this file only if the Kconfig value is set.

BRANCH=none
BUG=None
TEST=Build and run on Glados

Change-Id: I604f701057d7018f2ed9c3ba49a643c4bca13f00
Signed-off-by: Stefan Reinauer <reinauer@chromium.org>
Original-Commit-Id: c109481d9503916e19ed300c1a3f085e0d2b5c51
Original-Change-Id: I3214399f8156b5ea2ef709ce77e3915cea1523a3
Original-Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/248300
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Commit-Queue: Leroy P Leahy <leroy.p.leahy@intel.com>
Original-Tested-by: Leroy P Leahy <leroy.p.leahy@intel.com>
Reviewed-on: http://review.coreboot.org/9504
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig
index f7da89a..29f0514 100644
--- a/src/arch/x86/Kconfig
+++ b/src/arch/x86/Kconfig
@@ -84,6 +84,9 @@
 config BOOTBLOCK_NORTHBRIDGE_INIT
 	string
 
+config BOOTBLOCK_RESETS
+	string
+
 config HAVE_CMOS_DEFAULT
 	def_bool n