Blackfin arch: cplb and map header file cleanup

Blackfin arch: cplb and map header file cleanup

 - remove duplicated defines for the BF561
 - generalize L2 support (so that it works for BF54x) and mark it executable
 - add support for reading/executing the Boot ROM sections
   (since it has data/functions we may need at runtime)
 - and fixup names for each map

Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>