[Gandiva][C++] Fix castINTERVALDAY and castINTERVALYEAR

Fix error in LLVM where didn't find these two functions.

Fix regex to allow negative digits for Interval Day and Interval Year.

**Reporter**: [Johnnathan Rodrigo Pego de Almeida](https://issues.apache.org/jira/browse/ARROW-16108) / @Johnnathanalmeida
#### Externally tracked issue: [https://github.com/apache/arrow/pull/12776](https://github.com/apache/arrow/pull/12776)
#### PRs and other links:
- [GitHub Pull Request #12776](https://github.com/apache/arrow/pull/12776)

_{**Note**: *This issue was originally created as [ARROW-16108](https://issues.apache.org/jira/browse/ARROW-16108). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

The issue concerns Gandiva's C++ castINTERVALDAY and castINTERVALYEAR functions and their interval regex handling; no file or test is named. Review linked PR #12776 first, then locate the relevant Gandiva implementation and tests; done means LLVM finds both functions and negative Interval Day and Year digits are accepted.

Written by the indexing model from the issue text.