ARM: SPEAr600: Add device-tree support to SPEAr600 boards

ARM: SPEAr600: Add device-tree support to SPEAr600 boards

This patch adds a generic target for SPEAr600 board that can be
configured via the device-tree. Currently the following devices
are supported via the devicetree:

- VIC interrupts
- PL011 UART
- PL061 GPIO
- Synopsys DW I2C
- Synopsys DW ethernet

Other peripheral devices (e.g. SMI flash, FSMC NAND flash etc) will
follow in later patches.

Only the spear600-evb is currently supported. Other SPEAr600
based boards will follow later.

Since the current mainline SPEAr600 code only supports the SPEAr600
evaluation board, with nearly zero peripheral devices (only UART
and GPIO), it makes sense to switch over to DT based configuration
completely now. So this patch also removes all non-DT stuff, mainly
platform device data. The files spear600.c and spear600_evb.c are
removed completely.

Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>