[compiler-rt] Intercept the uname() function

Summary:
Move interceptor from msan to sanitizer_common_interceptors.inc, so that
other sanitizers could benefit.

Adjust FixedCVE_2016_2143() to deal with the intercepted uname().

Patch by Ilya Leoshkevich.

Reviewers: eugenis, vitalybuka, uweigand, jonpa

Reviewed By: eugenis, vitalybuka

Subscribers: dberris, krytarowski, #sanitizers, stefansf, Andreas-Krebbel

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D76578