tools: revert to using /var and /etc/

tools: revert to using /var and /etc/

26470:acaf29203cf9 "tools+stubdom: install under /usr/local by
default" moved more stuff under /usr/local than was desirable.

In particular SYSCONFIG_DIR (configuration for initscripts) moved to
/usr/local/etc/{sysconfig,defaults} while the initscripts themselves
(correctly) remained in /etc/init.d. Moving /etc/xen/scripts breaks
the udev bakcned rules file. Lastly stuff under /var was moved to
/usr/local/var.

Move these back to /etc/ and /var. Moving /etc wholesale rather thsn
just the problematic bits is preferable for consistency.

Although there seems to be some disagreement about /usr/local/var vs
/var using /var is compatible with the FHS and what we think most
people will expect.

Most of this impacts Linux only but NetBSD appears to have been using
/usr/local/var/lib which I have also reset to /var/lib.

Note that we already paid no attention to autoconf --sysconfdir or
--localstatedir ('etc' and 'var' respectively) so there is no change
from that PoV.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>