Fix LTO compilation error
Including <config.h> is required so that HAVE_WNCK is defined properly. Without it compilation fails when using LTO, with these flags: -flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing
with error:
type ‘struct MutableProcInfo’ violates the C++ One Definition Rule [-Werror=odr]