u-boot: add common inc file

SRCREV, SRC_URI, UBRANCH, etc. were duplicated across 3 recipes
so move them to a common include file.

Change-Id: I2a5e8e26b7d1aca3a2da285023812b555fe38407
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/common/recipes-bsp/u-boot/u-boot-mkimage_2016.07.bb b/common/recipes-bsp/u-boot/u-boot-mkimage_2016.07.bb
index 715eaf4..7f40435 100644
--- a/common/recipes-bsp/u-boot/u-boot-mkimage_2016.07.bb
+++ b/common/recipes-bsp/u-boot/u-boot-mkimage_2016.07.bb
@@ -1,15 +1,10 @@
 SUMMARY = "U-Boot bootloader image creation tool"
 LICENSE = "GPLv2+"
-LIC_FILES_CHKSUM = "file://Licenses/README;md5=a2c678cfd4a4d97135585cad908541c6"
 SECTION = "bootloader"
 
 DEPENDS = "openssl"
 
-SRCREV = "a5e0a21ed4b62ab4d8ff09f70b751db0f46ddaac"
-UBRANCH = "v2016.07-aspeed-openbmc"
-SRC_URI = "git://git@github.com/openbmc/u-boot.git;branch=${UBRANCH};protocol=https"
-
-PV = "v2016.07+git${SRCPV}"
+require u-boot.inc
 
 S = "${WORKDIR}/git"