[clang-tidy] Move fuchsia-restrict-system-includes to portability module for general use.
Summary:
Created a general check for restrict-system-includes under portability as recommend in the comments under D75332. I also fleshed out the user facing documentation to show examples for common use-cases such as allow-list, block-list, and wild carding.
Removed fuchsia's check as per phosek sugguestion.
Reviewers: aaron.ballman, phosek, alexfh, hokein, njames93
Reviewed By: phosek
Subscribers: Eugene.Zelenko, mgorny, xazax.hun, phosek, cfe-commits, MaskRay
Tags: #clang-tools-extra, #clang
Differential Revision: https://reviews.llvm.org/D75786