Remove use of 'xargs -0' from git-reset.

Even without the trouble it causes to people without GNU xargs,
it was not really necessary to print from Perl and then remove it
outside.  Just unlink it inside Perl.

Signed-off-by: Junio C Hamano <junkio@cox.net>

git-reset.sh

@@ -81,10 +81,12 @@ case "$reset_type" in
 		while (<$fh>) {
 			chomp;
 			if (! exists $keep{$_}) {
-				print "$_\0";
+				# it is ok if this fails -- it may already
+				# have been culled by checkout-index.
+				unlink $_;
 			}
 		}
-	' $tmp-exists | xargs -0 rm -f --
+	' $tmp-exists
 	;;
 --soft )
 	;; # Nothing else to do