[DOC] Updated README's for F0 and F4 examples to describe the needed board connections.

examples/stm32/f0/stm32f0-discovery/systick_blink/README

@@ -5,5 +5,10 @@ README
 This example is the same as fancy_blink except that it uses the systick timer
 to generate time accurate delays. The blue LED flashes four times per second.
 
-On pin PA9, there is MCO output of internal reference clock. This can be used
+There is internal reference clock available on MCO output pin. This can be used
 to debug the PLL clock setup by scope.
+
+Board connections:
+------------------
+
+  PA9	(MCO)	Internal reference clock