s7d: support mini fip layout, hybrid signing [1/1]

PD#SWPL-173221

Problem:
Need to support mini fip layout and hybrid signing

Solution:
merge it from s6

Verify:
./mk s7d_bm201 --former-sign --update-bl2 ...

Change-Id: I9f1acb17e5e6da9b637eaec1dbcaf80dbd25eed9
Signed-off-by: Lawrence Mok <lawrence.mok@amlogic.com>
22 files changed