Yabel : Add tracing option needed by i915tool.

This patch was made by listenning to what Ron Minnich told
  me to do on #coreboot IRC channel on Freenode with my
  adaptations on top.

i915tool is at https://code.google.com/p/i915tool/ ,
  the one in coreboot is outdated.

Change-Id: I13cd684f4c290114836fbd7babd461153e8d6124
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@no-log.org>
Reviewed-on: http://review.coreboot.org/3277
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/Kconfig b/src/Kconfig
index 24de7d2..fdf40e5 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -902,6 +902,15 @@
 
 	  If unsure, say N.
 
+config X86EMU_DEBUG_TIMINGS
+	bool "Output timing information"
+	default n
+	depends on X86EMU_DEBUG && UDELAY_LAPIC && HAVE_MONOTONIC_TIMER
+	help
+	  Print timing information needed by i915tool.
+
+	  If unsure, say N.
+
 config DEBUG_TPM
 	bool "Output verbose TPM debug messages"
 	default n