OMAP3: Move sr32() function to not duplicate code

OMAP3: Move sr32() function to not duplicate code

The sr32() function is implemented by various boards, this
patch moves this function to a common place to not duplicate code.

 board/omap3530beagle/omap3530beagle.c:215:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)
 board/igep00x0/igep00x0.c            :89:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)
 board/omap3430sdp/omap3430sdp.c      :103:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)
 board/omap3evm/omap3evm.c            :147:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)
 board/omap3430labrador/omap3430sdp.c :100:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)
 board/overo/overo.c                  :206:void sr32(u32 addr, u32 start_bit, u32 num_bits, u32 value)

Signed-off-by: Enric Balletbo i Serra <eballetbo@gmail.com>
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>