msg-filter: tweak path substitution for RHIVOS kernels

[kdudka]

... that use the el9_6iv dist tag. The regex we have been using did not accept the iv suffix.

Reported-by: Erico Nunes

[kdudka]

/packit rebuild-failed

[sfowl]

LGTM.

FWIW, looking at some internal data, suffixes like "el8_9.1" also seem somewhat common. Here's a few examples:

 autofs-5.1.4-109.el8_9.1
 avahi-0.7-21.el8_9.1
 bind-9.11.36-11.el8_9.1
 bind9.16-9.16.23-0.16.el8_9.2
 c-ares-1.13.0-9.el8_9.1

[kdudka]

Yes, this is the recommended versioning of Z-stream updates. These suffixes do not appear in file paths in scan results though. For example, if you look at the scan results of curl-8.12.1-1.el10 and curl-8.12.1-1.el10_0.1, the top-level directory is curl-8.12.1 in both the cases. So these results can be easily matched with each other without any transformation. The regex we are patching in this pull request is mostly used for Z-stream kernel builds, which use a very specific directory structure, as described in the commit message of f05aa13.