Fix UUID generation on FreeBSD.

UUID functions are in the standard C library on FreeBSD, while in Linux
they are pulled in from libuuid, which in turn comes from the extfs
progs.

Also the function prototypes and library types differ somewhat. This
patch adds #ifdefs where needed to make parted compile on FreeBSD.
Disable the libdl check on FreeBSD.

FreeBSD's standard C library contains this functionality, so there is no
libdl.
Disable device mapper support by default in FreeBSD.

Device mapper support is a Linux-specific extension, and not applicable
to FreeBSD where the necessary libraries do not exist.
Apply Debian patch "freebsd-geli.patch" as of version 2.3-12.
Apply Debian patch "freebsd-zvol.patch" as of version 2.3-12.
Apply Debian patch "freebsd-ufs.patch" as of version 2.3-12.
Apply Debian patch "kfreebsd-lvm.patch" as of version 2.3-12.
Fix incorrect error message in configure script.

We now support "freebsd" in addition to "linux", "gnu" and "beos".