gitweb/Makefile: fix typo in gitweb.min.css rule

This typo has been in place since the rule was originally added by
0e6ce21 (Gitweb: add support for minifying gitweb.css).

Signed-off-by: Jay Soffian <jaysoffian@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/gitweb/Makefile b/gitweb/Makefile
index f2e1d92..e7dd252 100644
--- a/gitweb/Makefile
+++ b/gitweb/Makefile
@@ -91,7 +91,7 @@
 GITWEB_CSS = gitweb.min.css
 all:: gitweb.min.css
 gitweb.min.css: gitweb.css GITWEB-BUILD-OPTIONS
-	$(QUIET_GEN)$(CSSMIN) <$ >$@
+	$(QUIET_GEN)$(CSSMIN) <$< >$@
 endif
 
 GITWEB_REPLACE = \