add comment on tbb patch

Author: lkeegan

build.sh

@@ -276,6 +276,7 @@ cd ../../
 git clone -b $TBB_VERSION --depth 1 https://github.com/oneapi-src/oneTBB.git
 cd oneTBB
 # patch for "c++.exe: fatal error: input file '/dev/null' is the same as output file" issue on windows due to cmake execute_process quoting command
+# line 50 of https://github.com/uxlfoundation/oneTBB/commit/377e6c3b1719f8cc7b68f9d0939e652d7e3bf776#diff-08a9ef6921a1ae25a4447b8a4ff5740038771e549fb6f0ff69dafb35c342a8b8R5
 # instead of calling c++ to get the binutils version we get it from CMAKE_CXX_COMPILER_LINKER_VERSION
 # note: this works fine for us as we use binutils for linker and assembler, haven't checked if it also works if a different linker is used.
 git apply --ignore-space-change --ignore-whitespace --verbose ../tbb.diff