platform: apply cflags += -mno-sched-prolog -mno-unaligned-access

From GCC manual,

-mno-sched-prolog
  Prevent the reordering of instructions in the function prologue, or the
  merging of those instruction with the instructions in the function's
  body.  This means that all functions start with a recognizable set of
  instructions (or in fact one of a choice from a small set of different
  function prologues), and this information can be used to locate the
  start of functions inside an executable piece of code.

-mno-unaligned-access
  Disables reading and writing of 16- and 32- bit values from addresses
  that are not 16- or 32- bit aligned.
include: fix KProbes function prototypes
apply strict compilation flags and fix function prototypes

Several functions in server/ were not specifying an argument list,
ie they were declared as void foo(); When compiling with -Wstrict-prototypes,
this leads to:
  platform/stm32f4/rcc.c:19:6: error: function declaration isn't a prototype
Merge pull request #35 from arcbbb/master

fixes issue #31
Makefile: scan mk/rules instead of hard-code

Fixes #53