scripts/omap_signGP: add getopt ...

Instead of using positional arguments add proper getopt support.
This also adds a help text.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Treewide: remove address of the Free Software Foundation ...

The FSF address has changed in the past. Instead of updating it
each time the address changes, just drop it completely treewide.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ARM omap: Add omap signGP tool and possibility to build ift images ...

The tool is needed to build images suitable for omap processors
to load from mmc or nand.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>