blackfin: bf60x: support big cplb page

BF60x support 16K, 64K, 16M and 64M cplb pages, this patch add support for them.
So that bf609-ezkit can use it's 128M memory.

Signed-off-by: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>