Zephyr deprecated and then removed its stack_analyze function because it
was unsafe. Use the new zephyr thread analyzer instead and rename the
MicroPython function to zephyr.thread_analyze() to be more consistent with
the implementation.
Tested on mimxrt1050_evk.
The output now looks like this:
>>> zephyr.thread_analyze()
Thread analyze:
80004ff4 : unused 400 usage 112 / 512 (21 %)
rx_workq : unused 1320 usage 180 / 1500 (12 %)
tx_workq : unused 992 usage 208 / 1200 (17 %)
net_mgmt : unused 656 usage 112 / 768 (14 %)
sysworkq : unused 564 usage 460 / 1024 (44 %)
idle : unused 256 usage 64 / 320 (20 %)
main : unused 2952 usage 1784 / 4736 (37 %)