Fall back on grepping for the revision number if no svn client is installed.

patch by Michel Bardiaux, mbardiaux mediaxim be

Originally committed as revision 6179 to svn://svn.ffmpeg.org/ffmpeg/trunk

version.sh

@@ -1,6 +1,8 @@
 #!/bin/sh
 
 svn_revision=`cd "$1" && LC_ALL=C svn info 2> /dev/null | grep Revision | cut -d' ' -f2`
+test $svn_revision || svn_revision=`cd "$1" && grep revision .svn/entries | \
+                                    cut -d '"' -f2 2> /dev/null`
 test $svn_revision || svn_revision=UNKNOWN
 
 NEW_REVISION="#define FFMPEG_VERSION \"SVN-r$svn_revision\""