Merge tag 'efi-2023-04-rc1-2' of https://source.denx.de/u-boot/custodians/u-boot-efi

Pull request for efi-2023-04-rc1-2

Documentation

* man-pages for source, blkcache, bdinfo
* fix references to distro documentation

UEFI:

* allow clear screen by scrolling
* ensure that file ubootefi.var is created
* fix CapsuleMax variable reporting

Others:

* reduce verbosity of fat_read_file()