[BUGFIX] Enable alt and link fields for page media

As the page.media in most cases is for images it makes
sense to enable the alt and link fields just like
tt_content.images.

This patch changes the default TCA for table pages so
the alt and link fields are enabled for the media
file_references.

Resolves: #56884
Releases: 6.2
Change-Id: I4496644d340a6fab9be18bf4942ea96a22b1b4ce
Reviewed-on: https://review.typo3.org/29816
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Reviewed-by: Nadir S.
Tested-by: Nadir S.
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn