[Blackfin][PATCH] Fix copyright and update license

board/bf533-ezkit/Makefile

board/bf533-ezkit/bf533-ezkit.c

board/bf533-ezkit/flash-defines.h

board/bf533-ezkit/psd4256.h

board/bf533-stamp/Makefile

board/bf533-stamp/bf533-stamp.c

board/bf533-stamp/bf533-stamp.h

board/bf537-stamp/bf537-stamp.c

board/bf537-stamp/flash-defines.h

board/bf537-stamp/flash.c

board/bf561-ezkit/bf561-ezkit.c

cpu/bf533/Makefile

cpu/bf533/bf533_serial.h

cpu/bf533/config.mk

cpu/bf533/cpu.c

cpu/bf533/cpu.h

cpu/bf533/flush.S

cpu/bf533/interrupt.S

cpu/bf533/interrupts.c

cpu/bf533/ints.c