meta-evb-ast2500: Add obmc-bsp-common.inc

Add obmc-bsp-common.inc so that evb-ast2500 build produces the OpenBMC
image.

Tested: Verify that the evb-ast2500 builds OK with below commands:

            TEMPLATECONF=meta-evb/meta-evb-aspeed/meta-evb-ast2500/conf . openbmc-env
            bitbake obmc-phosphor-image

(From meta-evb rev: 55bf3f1528d5c90c08c7cfa42e3f1783b4d29d35)

Signed-off-by: Lei YU <yulei.sh@bytedance.com>
Change-Id: I00b22e5fc9a99296028621abb29f40a44e99fc34
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/meta-evb/meta-evb-aspeed/meta-evb-ast2500/conf/local.conf.sample b/meta-evb/meta-evb-aspeed/meta-evb-ast2500/conf/local.conf.sample
index 6a12c60..0844090 100644
--- a/meta-evb/meta-evb-aspeed/meta-evb-ast2500/conf/local.conf.sample
+++ b/meta-evb/meta-evb-aspeed/meta-evb-ast2500/conf/local.conf.sample
@@ -19,3 +19,5 @@
 EXTRA_USERS_PARAMS = " \
   usermod -p '\$1\$UGMqyqdG\$FZiylVFmRRfl9Z0Ue8G7e/' root; \
   "
+
+require conf/machine/include/obmc-bsp-common.inc