Make it possible to install multiple kernel-debuginfo packages

Issue

• The rpm command refuses to install more than one kernel-*-debuginfo variant on a machine at a time, even though more than one kernel may be installed.
• The use-case is to have a systemtap compile-server, that has numerous kernel/kernel-devel/kernel-debuginfo/kernel-debuginfo-common package versions installed side-by-side. This is not possible due to conflicting files during install.