Update SPT page entry to change type from EXECUTABLE to PAGE_FILE to capture mmaps in addition to executables

src/userprog/process.c

@@ -706,7 +706,7 @@ load_segment (struct file *file, off_t ofs, uint8_t *upage,
 
       /* Add the page metadata to the SPT to be lazy loaded later on */
       if (page_insert (file, ofs, upage, page_read_bytes, page_zero_bytes,
-                       writable, PAGE_EXECUTABLE) == NULL)
+                       writable, PAGE_FILE) == NULL)
         return false;
 
       /* Advance. */