build-system: turn off lto=thin when building the fuzzers
With lto=thin the fuzzers fail as soon as they start with
ERROR: The size of coverage PC tables does not match the
number of instrumented PCs. This might be a compiler bug,
please contact the libFuzzer developers.
Also check https://bugs.llvm.org/show_bug.cgi?id=34636 for possible workarounds (tl;dr: don't use the old GNU ld)
M configure.ac M src/lxc/Makefile.am
Merge pull request #3802 from evverx/build-system-fuzzers