Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

fs/nfs/file.c

@@ -301,7 +301,7 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
  * disk, but it retrieves and clears ctx->error after synching, despite
  * the two being set at the same time in nfs_context_set_write_error().
  * This is because the former is used to notify the _next_ call to
- * nfs_file_write() that a write error occured, and hence cause it to
+ * nfs_file_write() that a write error occurred, and hence cause it to
  * fall back to doing a synchronous write.
  */
 static int