replace bashism with POSIX construct

Originally committed as revision 7317 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/configure b/configure
index d650955..113c458 100755 (executable)
--- a/configure
+++ b/configure
@@ -2066,7 +2066,7 @@ EOF
 
 pkgconfig_generate_uninstalled(){
 name=$1
-shortname=${name/lib/}
+shortname=${name#lib}
 comment=$2
 version=$3
 libs=$4