meta-bletchley: enable bletchley dts

select aspeed-bmc-facebook-bletchley.dts for build

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I85503d876b959a2f220ad84b6a9ddba047e89c80
diff --git a/meta-facebook/meta-bletchley/conf/machine/bletchley.conf b/meta-facebook/meta-bletchley/conf/machine/bletchley.conf
index b3480f5..d69357b 100644
--- a/meta-facebook/meta-bletchley/conf/machine/bletchley.conf
+++ b/meta-facebook/meta-bletchley/conf/machine/bletchley.conf
@@ -1,6 +1,5 @@
-#KMACHINE = "aspeed"
-#KERNEL_DEVICETREE = "${KMACHINE}-bmc-facebook-${MACHINE}.dtb"
-KERNEL_DEVICETREE = "aspeed-ast2600-evb.dtb"
+KMACHINE = "aspeed"
+KERNEL_DEVICETREE = "${KMACHINE}-bmc-facebook-${MACHINE}.dtb"
 
 UBOOT_MACHINE = "ast2600_openbmc_spl_defconfig"
 UBOOT_DEVICETREE = "ast2600a1-evb"