i2c: xgene-slimpro: Support v2

This patch supports xgene-slimpro-i2c v2 which uses the non-cachable memory
as the PCC shared memory.

Signed-off-by: Hoan Tran <hotran@apm.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>