Pull request for UEFI sub-system for efi-2020-07-rc1
This pull request
* provides an implementation of UEFI secure booting
* fixes a problem with the rsa_mod_exp driver which stops some boards
from booting when CONFIG_RSA is enabled which is needed for UEFI
secure booting
* enables the EFI_RNG_PROTOCOL if DM_RNG is enabled
* fixes some function comments