Bug 189911

Mapping a shared library to another - existing or not existing - library
via LD_LIBMAP, as described in rtld(1), has no effect (but it does work
when done in libmap.conf).

Fix: The following patch is against 10-STABLE, but should apply to HEAD as
well.

It seems that, due to an oversight in HEAD r232862, lmc_parse() was
passed wrong arguments in the libmap_override case.
How-To-Repeat: $ LD_LIBMAP=libncurses.so.8=libncurses.so.5 ldd /bin/ls
/bin/ls:
	libutil.so.9 => /lib/libutil.so.9 (0x800823000)
	libncurses.so.8 => /lib/libncurses.so.8 (0x800a35000)
	libc.so.7 => /lib/libc.so.7 (0x800c82000)

On the other hand, with

$ cat /etc/libmap.conf
[ls]
libncurses.so.8 libncurses.so.5
$ 

we get

$ ldd /bin/ls
/bin/ls:
	libutil.so.9 => /lib/libutil.so.9 (0x800823000)
	libncurses.so.8 => /usr/local/lib/libncurses.so.5 (0x800a35000)
	libc.so.7 => /lib/libc.so.7 (0x800c53000)
	libtinfo.so.5.9 => /usr/local/lib/libtinfo.so.5.9 (0x800ffa000)
$ 

if  libncurses.so.5 from the devel/ncurses port exists.

Otherwise, we get

$ ldd /bin/ls
/bin/ls:
	libutil.so.9 => /lib/libutil.so.9 (0x800823000)
	libncurses.so.8 => not found (0)
	libc.so.7 => /lib/libc.so.7 (0x800a35000)
$