[PATCHv2 0/6] Rework the BLK symbol usage in Kconfig

Hey all,

One problem we have today is how the BLK symbol is set and used in Kconfig files. Part of the challenge is that we use it as a gating symbol for "we have a block device" and also for "enable block device library code". What this series does is move to always use "select BLK" by block drivers (a few were and a few others had it the inverse) and then "depends on BLK" for functionality that needs a block device present. The end result of this series is that a number of platforms which had disabled EFI_LOADER now don't ask for it (they have no block device) and espresso7420 has a regression about MMC support fixed. With v2 of this I've picked up the review tags from v1 and also reworded the body of the commit in the first patch.