Moved flight make code into flight/Makefile. This should speed up
rebuilds for GCS and keeps the top level Makefile tidier.
Change-Id: I9d33cb5c223b6a8ed2821435a5d63ecf4b97c6b8
Moves the CMSIS system_stm3210x.c from library.mk to the individual Makefiles for the F1 targets. This allows for custom SystemInit functions where necessary.