Change order of includes in apps/Makefile; add clock frequencies to shenzhou,...

Change order of includes in apps/Makefile; add clock frequencies to shenzhou, fire, and olimex-stm32 board.h files

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5210 42af7a65-404d-4744-a932-0658087f49c3