configure: reference the README for missing yasm

Change-Id: I2ad799901385011764affadeaddcc271df21509f

build/make/configure.sh

diff --git a/build/make/configure.sh b/build/make/configure.sh
index 9c30441..73e4c63 100644
--- a/build/make/configure.sh
+++ b/build/make/configure.sh
@@ -1167,7 +1167,8 @@
               && AS=""
           fi
           [ "${AS}" = auto ] || [ -z "${AS}" ] \
-            && die "Neither yasm nor nasm have been found"
+            && die "Neither yasm nor nasm have been found." \
+                   "See the prerequisites section in the README for more info."
           ;;
       esac
       log_echo "  using $AS"