sanitizers: switch BlockingMutex(LINKER_INITIALIZED) to Mutex

Mutex does not support LINKER_INITIALIZED support.
As preparation to switching BlockingMutex to Mutex,
proactively replace all BlockingMutex(LINKER_INITIALIZED) to Mutex.
All of these are objects with static storage duration and Mutex ctor
is constexpr, so it should be equivalent.

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D106944