include: Add a MIN macro.

include/libssh/priv.h

@@ -223,8 +223,9 @@ int decompress_buffer(ssh_session session,ssh_buffer buf, size_t maxlen);
 /* match.c */
 int match_hostname(const char *host, const char *pattern, unsigned int len);
 
-
-
+#ifndef MIN
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+#endif
 
 /** Free memory space */
 #define SAFE_FREE(x) do { if ((x) != NULL) {free(x); x=NULL;} } while(0)