Doc: Link CMake variable and property pages to the new how-to page


Add a link to "Setting CMake variables and properties" to every
documented CMake variable and property page. That page explains how to
set variables and properties in a project, on the command line, and in
IDEs.

Task-number: QTBUG-122379
Pick-to: 6.12
Change-Id: Ifcf45d59163e130c3316067b696a0d81c3374309
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
commit2138affc8182a45f2e9b8715f22136c409cc178f
parent7df49d768500d25df3f460f1fc0cfd3ec4f1fca7
authorJoerg Bornemann <joerg.bornemann@qt.io>
committerJoerg Bornemann <joerg.bornemann@qt.io>
commit timeMon, 12 Oct 2026 15:43:24 +0000