ftp/wzdftpd: fix build with LLVM 15
Seems like the compiler got a whole lot stricter with this release.
The biggest fix was changing the thread ID from unsigned long to
pthread_t, which will probably break compilation on Win32.
While we are at it, replace static uses of REINPLACE_CMD with patch
files as per policy. This change is responsible for most of the
newly added patches.
The wzdftpd build scripts want to install plugins into ${PREFIX}/share
when they belong into ${PREFIX}/lib. Instead of patching this in each
Makefile.am, set --datadir=${PREFIX}/lib and work around the one file
for which this is wrong.
Approved by: eduardo (mentor)
Differential Revision: https://reviews.freebsd.org/D38523