zlib: fix code when DEBUG is defined

Removed stdio.h inclusion and moved trace macros to use printf avoiding to
write debug informations to standard error.

Signed-off-by: Giuseppe Condorelli <giuseppe.condorelli@st.com>
diff --git a/lib_generic/zlib.c b/lib_generic/zlib.c
index 1b6db32..8fe3bd0 100644
--- a/lib_generic/zlib.c
+++ b/lib_generic/zlib.c
@@ -27,6 +27,7 @@
 #define ZLIB_INTERNAL
 
 #include "u-boot/zlib.h"
+#include <common.h>
 /* To avoid a build time warning */
 #ifdef STDC
 #include <malloc.h>
@@ -83,10 +84,10 @@
 
 /* Diagnostic functions */
 #ifdef DEBUG
-#include <stdio.h>
 	extern int z_verbose;
 	extern void z_error    OF((char *m));
 #define Assert(cond,msg) {if(!(cond)) z_error(msg);}
+#define fprintf(fp,...)	printf(__VA_ARGS__)
 #define Trace(x) {if (z_verbose>=0) fprintf x ;}
 #define Tracev(x) {if (z_verbose>0) fprintf x ;}
 #define Tracevv(x) {if (z_verbose>1) fprintf x ;}
@@ -2000,7 +2001,7 @@
     char *m;
 {
 	fprintf(stderr, "%s\n", m);
-	exit(1);
+	hang ();
 }
 #endif