meta-x86: Add support for gatesgarth

(From meta-x86 rev: 8d69ba4a50fa04545e0924fdcf9ecf6bc1e43e66)

Change-Id: I0ad76bd877f956746931644a4686fb80ed685865
Signed-off-by: Jason M. Bills <jason.m.bills@linux.intel.com>
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-x86/conf/layer.conf b/meta-x86/conf/layer.conf
index 988bd23f..d10e210 100644
--- a/meta-x86/conf/layer.conf
+++ b/meta-x86/conf/layer.conf
@@ -3,4 +3,4 @@
 
 BBFILE_COLLECTIONS += "obmc_machines_x86"
 BBFILE_PATTERN_obmc_machines_x86 = ""
-LAYERSERIES_COMPAT_obmc_machines_x86 = "dunfell"
+LAYERSERIES_COMPAT_obmc_machines_x86 = "dunfell gatesgarth"