build system: rename __BOOT_BLOCK__ and __VER_STAGE__

Drop the inner underscore for consistency. Follows the
commit stated below.

Change-Id: I75cde6e2cd55d2c0fbb5a2d125c359d91e14cf6d
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Based-on-Change-Id: I6a1f25f7077328a8b5201a79b18fc4c2e22d0b06
Based-on-Signed-off-by: Julius Werner <jwerner@chromium.org>
Based-on-Reviewed-on: https://chromium-review.googlesource.com/219172
Reviewed-on: http://review.coreboot.org/9290
Reviewed-by: Aaron Durbin <adurbin@google.com>
Tested-by: build bot (Jenkins)
10 files changed