runtests.c: Mark some sections as to be excluded by clang-format
runtests.c: Mark some sections as to be excluded by clang-format

This will make clang-format 9 produce stable results.

libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat,libexpat/libexpat