ARM: pxa: magician: Fix support for Intel Strata NOR Flash

Old definition for the physmap-flash driver is incomplete:
- Use of an EGPIO without previous request
- Missing the MTD partitions

This patch fixes it. Read functionality was tested on the machine with
board_id 0x3a. Writing was not tested.

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>