meta: scripts - relocation script adapted to support big-endian machines

meta: scripts - relocation script adapted to support big-endian machines

relocate_sdk.py was developed for little-endian architures and when tries
to install SDK for big-endian machines errors like below will be shown.
Error: struct.error: unpack requires a string argument of length 32. SDK could
not be set up. Relocate script failed. Abort!
Error: IOError: [Errno 22] Invalid argument. SDK could not be set up. Relocate
script failed. Abort!

To fix this, script is modified to support big-endian architecture.

Signed-off-by: Sundeep KOKKONDA <sundeep.kokkonda@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>