The freq_ctr app is a small application that is implementing a
simplistic direct-mode frequency counter using the internal 32.768kHz
oscillator and two TC blocks. One of them is used to generate a 1Hz
signal, which is then subsequently used by the other TC to trigger
a counter read after exactly 1s.
This is in itself not something useful on a simtrace2 device. However,
it is a separate 'app' and I prefer to have the code here in master
over some obscure branch that's easy to forget about.
Change-Id: I2249bfb8dd6a88d85d406f3b33537377133d0939
