Corresponds to Cygwin's 1.4.17-4.
Additional patch to not build lssparse if SEEK_HOLE is not defined in
unistd.h, as it is not on runtime versions < 3.6.
In some cases this will introduce cycles which could likely be cleaned
up by only depending on some unix tools instead of the whole autotools.
Rebuilding doesn't make much sense at this point since it just adds a subset
of base-devel which is still installed by default.
