rtfm framework periodic.rs does not work anymore

[jjkt]

Something has regressed on periodic.rs example, it does not print the expected output anymore.

[jjkt]

Additionally, on latest cortex-rtic, the example does not compile anymore..

[jjkt]

With the recent RTIC b87fca3d21d92018ac4d50b200cf8e77cb577028 version the "foo" is printed 4 times, but the timing interval was not 1 second. This is because the example has been tuned to 12MHz speed on QEMU and zmu does not have timing control as of now