fix_issue583_Remove unnecessary null pointer checks

[enkilee]

fix_issue583_remove_nullpoint: https://github.com/PaddlePaddle/CINN/issues/583 del: An extra null pointer check is not needed in functions like the following.

Buffer::DeallocHost Shape::Resize

[luotao1]

Would an other commit message be more helpful?

@elfring What do you mean about an other commit message?

[elfring]

:thought_balloon: I suggest to improve commit messages according to known information sources.

[luotao1]

Please provide an improved merge/pull request with consistent changes.

@enkilee You can update the PR title and improve the PR description.

[elfring]

:thinking: Would you like to take further update candidates into account?

[zhhsplendid]

🤔 Would you like to take further update candidates into account?

Sure, we will try to fix more places like these in the near future. @elfring Thank you for the code improvement suggestion.