Revert "[MTE] Add -fsanitize=memtag* and friends."

clang/include/clang/Basic/DiagnosticDriverKinds.td

clang/include/clang/Basic/Features.def

clang/include/clang/Basic/Sanitizers.def

clang/include/clang/Driver/Options.td

clang/include/clang/Driver/SanitizerArgs.h

clang/lib/CodeGen/CGDeclCXX.cpp

clang/lib/CodeGen/CodeGenFunction.cpp

clang/lib/CodeGen/CodeGenModule.cpp

clang/lib/Driver/SanitizerArgs.cpp

clang/lib/Driver/ToolChains/CommonArgs.cpp

clang/test/CodeGen/memtag-attr.cpp

clang/test/Driver/fsanitize.c

clang/test/Driver/memtag-ld.c

clang/test/Driver/memtag.c

clang/test/Lexer/has_feature_memtag.cpp

clang/test/Lexer/has_feature_memtag_sanitizer.cpp