Merge tag 'efi-2021-04-rc1-4' of https://gitlab.denx.de/u-boot/custodians/u-boot-efi

Pull request for UEFI sub-system for efi-2021-04-rc1-4

Bug fixes:

* re-read the partition table after writing GPT
* fix a problem booting ARMv7 boards with PSCI without UEFI
* make aarch64 UEFI test programs compatible with GRUB linux command
* correct the alignment check in the EFI_BLOCK_IO_PROTOCOL
* check EFI_BLOCK_IO_PROTOCOL.Media->LastBlock in unit test