cmake build: don't hardcode absolute paths in install DESTINATIONs

[fogti]

Fixes #683

[lxbsz]

This seems incorrect:

Currently the install paths will be:

Install the project...
-- Install configuration: ""
-- Up-to-date: /usr/lib64/libtcmu.so.2.2
-- Up-to-date: /usr/lib64/libtcmu.so.2
-- Up-to-date: /usr/lib64/libtcmu.so
-- Up-to-date: /usr/bin/tcmu-runner
-- Up-to-date: /usr/lib64/tcmu-runner/handler_file_optical.so
-- Up-to-date: /usr/lib64/tcmu-runner/handler_file_zbc.so
-- Up-to-date: /usr/lib64/tcmu-runner/handler_rbd.so
-- Up-to-date: /usr/lib64/tcmu-runner/handler_qcow.so
-- Up-to-date: /etc/tcmu//tcmu.conf.old
-- Installing: /etc/tcmu//tcmu.conf
-- Up-to-date: /etc/logrotate.d/tcmu-runner.bak/tcmu-runner
-- Installing: /etc/logrotate.d/tcmu-runner
-- Up-to-date: /usr/share/dbus-1/system-services/org.kernel.TCMUService1.service
-- Up-to-date: /etc/dbus-1/system.d/tcmu-runner.conf
-- Up-to-date: /usr/lib/systemd/system/tcmu-runner.service
-- Up-to-date: /usr/share/man/man8/tcmu-runner.8

With this:

Install the project...
-- Install configuration: ""
-- Installing: /usr/lib64/libtcmu.so.2.2
-- Up-to-date: /usr/lib64/libtcmu.so.2
-- Up-to-date: /usr/lib64/libtcmu.so
-- Installing: /usr/bin/tcmu-runner
-- Set runtime path of "/usr/bin/tcmu-runner" to ""
-- Installing: /usr/lib64/tcmu-runner/handler_file_optical.so
-- Installing: /usr/lib64/tcmu-runner/handler_file_zbc.so
-- Installing: /usr/lib64/tcmu-runner/handler_rbd.so
-- Installing: /usr/lib64/tcmu-runner/handler_qcow.so
-- Installing: /data/tcmu-runner/etc/tcmu/tcmu.conf
-- Installing: /data/tcmu-runner/etc/logrotate.d/tcmu-runner
-- Up-to-date: /usr/share/dbus-1/system-services/org.kernel.TCMUService1.service
-- Installing: /usr/etc/dbus-1/system.d/tcmu-runner.conf
-- Installing: /usr/lib/systemd/system/tcmu-runner.service
-- Installing: /usr/share/man/man8/tcmu-runner.8

[fogti]

ok, this means ${CMAKE_INSTALL_SYSCONFDIR} gets at one point resolved to /data/tcmu-runner/etc and at another to /usr/etc, both of which are surprising..., although I don't know why exactly.

might be fixable using set(CMAKE_INSTALL_SYSCONFDIR CACHE PATH /etc) or so...

[fogti]

I have replaced the confusing usage of file(INSTALL) with more appropriate commands... And regarding the interpretation of CMAKE_INSTALL_SYSCONFDIR the problem exists that both ${CMAKE_INSTALL_PREFIX}/etc and /etc are reasonable choices, and it should be specified anyways...

[fogti]

and I now changed the usage from ${CMAKE_INSTALL_SYSCONFDIR} to ${CMAKE_INSTALL_FULL_SYSCONFDIR}, which should have the correct value.

[lxbsz]

Install the project...
-- Install configuration: ""
-- Installing: /usr/lib64/libtcmu.so.2.2
-- Up-to-date: /usr/lib64/libtcmu.so.2
-- Up-to-date: /usr/lib64/libtcmu.so
-- Installing: /usr/bin/tcmu-runner
-- Set runtime path of "/usr/bin/tcmu-runner" to ""
-- Installing: /usr/lib64/tcmu-runner/handler_file_optical.so
-- Installing: /usr/lib64/tcmu-runner/handler_file_zbc.so
-- Installing: /usr/lib64/tcmu-runner/handler_rbd.so
-- Installing: /usr/lib64/tcmu-runner/handler_qcow.so
CMake Error at tcmu.conf_install.cmake:4 (install):
  install command is not scriptable
Call Stack (most recent call first):
  cmake_install.cmake:157 (include)


make: *** [Makefile:106: install] Error 1