Provide ability to integrate with QComm SBLs

Ipq8064 SBLs initialize the hardware to prepare it to run an arbitrary
user provided bootloader. The only bootloader requirements imposed by
the SBLs are that it is concatenated with the SBL chunks in the
bootprm AND it uses MBN encapsulation (mostly to specify the size and
load address).

This patch adds configuration options to specify the location of the
SBL blobs and to require MBN encapsulation of the bootblock.

BRANCH=none
BUG=chrome-os-partner:27784
TEST=manual

  - the below demonstrates added encapsulation, no code run attempts
    have been made yet:

    $ FEATURES=noclean emerge-storm coreboot
    $ cd /build/storm/tmp/portage/sys-boot/coreboot-9999/work/coreboot-9999
    $ \od -t x4 build/cbfs/fallback/bootblock.bin | head -3
    0000000 00000005 00000003 00000000 2a010000
    0000020 00000be0 00000be0 2a010be0 00000000
    0000040 2a010be0 00000000 e32bf0df e59f0030

Original-Change-Id: Iae30ad08059e2b35c434ac25a410ac2017752957
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/193511
(cherry picked from commit bf16ea915c723ab124d817e3b0d950282e3cf1c1)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I53c71d382ec1d826f530d7afb545f64ec4eaf96b
Reviewed-on: http://review.coreboot.org/7261
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2 files changed