ARM: 7515/1: integrator: check PL010 base address from resource

In the PL010 UART callback a comparison against the location of the
statically allocated PL010 device is done to figure out which UART
is doing the callback. This does not play well with dynamic devices
such as in device tree, so let's check the base address of the
memory resource inside the amba_device instead.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>