[compiler-rt] Disabled tests and benchmarks for libc++

We don't run tests or benchmarks from this build anyway.
Benchmarks in custom libc++ break my local build.

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D115375

compiler-rt/cmake/Modules/CustomLibcxx/CMakeLists.txt

@@ -25,5 +25,7 @@ set(LIBCXX_CXX_ABI "libcxxabi" CACHE STRING "")
 set(LIBCXX_CXX_ABI_INTREE 1)
 set(LIBCXX_ENABLE_STATIC_ABI_LIBRARY ON CACHE BOOL "")
 set(LIBCXX_CXX_ABI_INCLUDE_PATHS ${COMPILER_RT_LIBCXXABI_PATH}/include CACHE PATH "")
+set(LIBCXX_INCLUDE_BENCHMARKS OFF CACHE BOOL "")
+set(LIBCXX_INCLUDE_TESTS OFF CACHE BOOL "")
 
 add_subdirectory(${COMPILER_RT_LIBCXX_PATH} ${CMAKE_CURRENT_BINARY_DIR}/cxx)