website: clean warnings to links in status reports

[vladlen]

Summary

website build generates many warnings due to possible wrong links.

1. Wrong links fixed.
2. Links in freebsd-foundation placed under ifdef construct:

a) _index.adoc declares reports-path variable and includes
all files.
b) in freebsd-foundation the check is added:
ifdef::reports-path[]
links for included or standalone file have different format, f.e.:

ifdef::reports-path[]
<<_cyber_resilience_act_cra_readiness_project,Cyber Resilience Act (CRA) Readiness Project>>.
endif::[] 
ifndef::reports-path[]
link:../cra[Cyber Resilience Act (CRA) Readiness Project].
endif::[]