The SRAM PA addresses are locally defined and used at
different places, i.e. SRAM management code and idle sleep code.

The macros are now defined at a centralized place, for
easier maintenance.

Tested on N900 and Beagleboard with full RET and OFF modes,
using cpuidle and suspend.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Nishanth Menon<nm@ti.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>