filelist2content: Do not strip whitespace from filenames

Set IFS to the empty string when reading the filenames to avoid leading
or trailing whitespace to be stripped from the name.

It's not unlikely that other components of bee fail on filenames with
trailing spaces, too, but that is not a reason to keep the bug in this
tool.

src/filelist2content.sh.in

@@ -64,7 +64,7 @@ function do_f2c() {
         exit 1
     fi
 
-    while read -r filename ; do
+    while IFS='' read -r filename ; do
         data=$(stat --format "$(get_format_string)" "${root}${filename}")
 
         if [ "$?" -gt 0 ] ; then