meta-bletchley: bsp: convert patch to cfg file

convert current patch to .cfg file

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I98ad0d5d69dd0c55ea40debd5b05ba4aa77be945
diff --git a/meta-facebook/meta-bletchley/recipes-bsp/u-boot/u-boot-fw-utils-aspeed-sdk_%.bbappend b/meta-facebook/meta-bletchley/recipes-bsp/u-boot/u-boot-fw-utils-aspeed-sdk_%.bbappend
index c9401d1..de2bc50 100644
--- a/meta-facebook/meta-bletchley/recipes-bsp/u-boot/u-boot-fw-utils-aspeed-sdk_%.bbappend
+++ b/meta-facebook/meta-bletchley/recipes-bsp/u-boot/u-boot-fw-utils-aspeed-sdk_%.bbappend
@@ -1,5 +1,2 @@
 FILESEXTRAPATHS:prepend := "${THISDIR}/u-boot-aspeed-sdk:"
-
-SRC_URI += " \
-            file://0001-u-boot-ast2600-57600-baudrate-for-bletchley.patch \
-           "
+SRC_URI +="file://bletchley.cfg"