Remove trailing whitespace.

Also, the script is a one-liner, stolen from [1]:

ack --print0 -l '[ \t]+$' | xargs -0 -n1 perl -pi -e 's/[ \t]+$//'

[1]
https://stackoverflow.com/questions/149057/how-to-remove-trailing-whitespace-of-all-files-recursively

util/wmaker.inst.in

@@ -35,7 +35,7 @@ make_script() {
 	ISCRIPT="$1"
 
 	cat << EOF >> "$ISCRIPT"
-# Window Maker default X session startup script 
+# Window Maker default X session startup script
 
 PATH="\$PATH:$BINDIR"