Merge topic 'backport-4.2-cmake-P-script-case' into release-4.2

a2f1866d86 Merge branch 'backport-4.0-cmake-P-script-case'
a3358bb66a cmake: Restore normalization of `-P` script to on-disk path

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !11930