Fixes a build error with GCC 4.5.1.

Signed-off-by: Lucas C. Villa Real <lucasvr@gobolinux.org>

--- fcgi-2.4.0/libfcgi/fcgio.cpp.orig	2011-02-02 18:11:29.000000000 -0200
+++ fcgi-2.4.0/libfcgi/fcgio.cpp	2011-02-02 18:12:38.000000000 -0200
@@ -25,6 +25,10 @@
 #include <limits.h>
 #include "fcgio.h"
 
+#ifndef EOF
+#define EOF -1
+#endif
+
 using std::streambuf;
 using std::istream;
 using std::ostream;