Merge pull request #5397 from OTAkeys/pr/stm32f2xx

boards/nucleo-f207/Makefile

boards/nucleo-f207/Makefile.features

boards/nucleo-f207/Makefile.include

boards/nucleo-f207/board.c

boards/nucleo-f207/dist/openocd.cfg

boards/nucleo-f207/include/board.h

boards/nucleo-f207/include/periph_conf.h

cpu/stm32f2/Makefile

cpu/stm32f2/Makefile.include

cpu/stm32f2/cpu.c

cpu/stm32f2/include/cpu_conf.h

cpu/stm32f2/include/periph_cpu.h

cpu/stm32f2/include/stm32f205xx.h

cpu/stm32f2/include/stm32f207xx.h

cpu/stm32f2/include/stm32f215xx.h

cpu/stm32f2/include/stm32f217xx.h

cpu/stm32f2/ldscripts/stm32f205rg.ld

cpu/stm32f2/ldscripts/stm32f207zg.ld

cpu/stm32f2/ldscripts/stm32f215rg.ld

cpu/stm32f2/ldscripts/stm32f215ve.ld