Refactored NumericLiteralParser to not require a Preprocessor

Summary:
We would like to use NumericLiteralParser in the implementation of the
syntax tree builder, and plumbing a preprocessor there seems
inconvenient and superfluous.

Reviewers: eduucaldas

Reviewed By: eduucaldas

Subscribers: gribozavr2, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83480