Support AIX 7

[ngarratt]

A number of small changes to support building and installing on AIX 7

1. Report errors during make install
2. Add queue.h for the TAILQ macros required by imsg
3. Link to pthread
4. Add a shim for the AIX version of 'install', which is missing -b/-d options and support for target filenames. Too many uses of these to wrap ifdefs around them individually
5. Add AR_FLAGS to OSSEC_LINK, to support -X64
6. Rename __version to __ossec_version, to avoid a naming conflict with _LC_object_t in sys/lc_core.h
7. Support mkgroup move from /usr/sbin/mkgroup to /usr/bin/mkgroup
8. Allow ksh to test for the user not existing in passwd (doesn't support [ ! ... ], and test isn't required in that case)
9. Use a default shell if /bin/false is not authorized in /etc/security/login.cfg

[atomicturtle]

Just verified this on AIX 7.3 Power 10 architecture. Looks good, with a minor conflict fix