[rhythmbox] autogen: fail noisily if yelp-tools can't be found

[Jonathan Matthew <jmatthew src gnome org>]

commit 67899c221cab2c26ecbaafc0845b2818c2518fc6
Author: Jonathan Matthew <jonathan d14n org>
Date:   Mon Jun 3 21:02:32 2013 +1000

    autogen: fail noisily if yelp-tools can't be found

 autogen.sh |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/autogen.sh b/autogen.sh
index 0e77a1c..8888ec9 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -30,6 +30,13 @@ if test -z `which autopoint`; then
         exit 1
 fi
 
+
+ACDIR=`${ACLOCAL:-aclocal} --print-ac-dir`
+if ! test -f $ACDIR/yelp.m4; then
+       echo "*** No yelp-tools found, please install it ***"
+       exit 1
+fi
+
 # Need to mkdir -p the m4 directory in case it doesn't exist, to prevent
 # gtkdocize from failing.
 mkdir -p m4