With --enable-pch=full there's not much difference between a "public"
header in <module>/inc and a private one in <module>/src/somewhere/inc .
And since the script searches recursively, this apparently helps to
find even more headers for lower pch levels.

Change-Id: I8483d0aa5b4fea5a59107c20a8aa5f1ef694af0a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87799
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

I think this is all external libs where it makes sense for them
to have their own PCH and be worth it. Maybe some smaller externals
can also use the common system PCH, but unfortunately many externals
use all kinds of defines that affect system headers, which is
a problem for the common system PCH.

Change-Id: I2c589ac55d93728daf3b158df110722e5f055d45
Reviewed-on: https://gerrit.libreoffice.org/80728
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>