ARM: PRIMA2: enable AUTO_ZRELADDR for SIRF in Kconfig

prima2 and marco have different memory base address. prima2
begins from 0 and marco begins from 0x40000000.
This patch enables AUTO_ZRELADDR so that kernel can detect
the physical address automatically.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
CC: Mark Rutland <mark.rutland@arm.com>