Every CPack generator sets default CPACK_PACKAGING_INSTALL_PREFIX
variable value differently so test framework should support
that correctly - previous version expected RPM/Deb /usr default and
removed it for Archive packagers as the default there is /.
Adds support for epoch version to CPackRPM and
CPackDeb packagers.
Also adds better version checking to CPackDeb
that complies with Debian rules.
Fixes: #17057