improve System Control Module defines

improve System Control Module defines

This patch:

- prefaces the SCM register offsets with the appropriate platform string
  (e.g., OMAP2_ for 24xx/34xx-common registers) and updates code that uses
  these registers to use the correct name;

- adds some more register bit defines (e.g., OMAP2_DEVICETYPE_MASK) and
  cleans up code to use these common macros;

- fixes the offset of the CONTROL_STATUS register on 24xx that partially
  caused SRAM patcher problems (with thanks to Kyungmin Park
  <kmpark@infradead.org> for finding this problem)

- adds many more register offset defines for the 'GENERAL' section of the
  SCM.

Boot-tested on N800 and 2430SDP.  3430SDP is down at the moment, so
can't test there.  Incidentally, on N800, there is no vmlinux size
difference between unpatched and patched kernels.  Comments welcome.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>