Fixes warnings from MSVC

programs/fuzz/common.c

@@ -26,7 +26,10 @@ int dummy_send( void *ctx, const unsigned char *buf, size_t len )
     (void) buf;
 
     //pretends we wrote everything ok
-    return( len );
+    if (len > INT_MAX) {
+        return -1;
+    }
+    return int( len );
 }
 
 int fuzz_recv( void *ctx, unsigned char *buf, size_t len )

programs/fuzz/onefile.c

@@ -1,5 +1,4 @@
 #include <stdint.h>
-#include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>