The links to the versioned libcriu.so.* included $(DESTDIR) and
$(LIBDIR) which will generate wrong links if building criu packages.
Now the links points to the correct file without any path.

For some reason criu.8 was installed with executable permission. Use
'install' with '-m 644' to make sure this does not happen.
Signed-off-by: Adrian Reber <adrian@lisas.de>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>