[fuzz] make the custom loader to handle multiple files

Actually this was the way it used to work :)

test/fuzzing/main.cc

@@ -1,28 +1,25 @@
 #include "hb-fuzzer.hh"
 
 #include <stdio.h>
-#include <stdlib.h>
-#include <assert.h>
 
 int main (int argc, char **argv)
 {
-  hb_blob_t *blob = hb_blob_create_from_file (argv[1]);
+  for (int i = 1; i < argc; i++)
+  {
+    hb_blob_t *blob = hb_blob_create_from_file (argv[i]);
 
     unsigned int len;
     const char *font_data = hb_blob_get_data (blob, &len);
     if (len == 0)
     {
       printf ("Font not found.\n");
-    exit (1);
+      return 1;
     }
 
-  for (int i = 1; i < argc; i++)
-  {
     printf ("%s\n", argv[i]);
     LLVMFuzzerTestOneInput ((const uint8_t *) font_data, len);
-  }
 
     hb_blob_destroy (blob);
-
+  }
   return 0;
 }