armv7a_mmu: Add support for decoding Super Sections

armv7a_mmu: Add support for decoding Super Sections

The ARMv7-A architecture supports super sections which allows mapping
physical addresses up to 40-bit into a 32-bit virtual address using the
short descriptor format (see ARM DDI 0406C.c section B4.1.112 for
details).

Change-Id: I8e64d0e93e36ae7a7da7b7bf2a8342856bb044f1
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-on: http://openocd.zylin.com/5212
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>