Patch "sanitizer_common: modernize SpinMutex" added default
ctor to StaticSpinMutex. But it broke some gcc bots with:
scudo_tsd_exclusive.cpp:25:22: error: non-local variable
‘__scudo::TSD’ declared ‘__thread’ needs dynamic initialization
https://lab.llvm.org/buildbot/#/builders/105/builds/12649
Unfortunatly none of empty ctor {}, no ctor, default constexpr ctor
work for different reasons. So remove StaticSpinMutex ctor
entirely and move deleted copy ctor back to SpinMutex.
Differential Revision: https://reviews.llvm.org/D106424
74b8fca9e4