This file is actually port-generic and should be moved out of stmhal/ .
Other ports already use it, and thus it should use mp_hal_ticks_ms()
right away.

Since we now have it.

These MPHAL functions are intended to replace previously used HAL_Delay(),
HAL_GetTick() to provide better naming and MPHAL separation (they are
fully equivalent otherwise).

Also, refactor extmod/modlwip to use them.

Like foo.bar or foo->bar.

With MicroPython codestyle, with pointer casts, "*" packs with primary type
without space. Few other similar changes too (git diff -b -w is null).

Based on the original patch by Galen Hazelwood:
https://github.com/micropython/micropython/pull/1517 .

This is required to write structures to files, pass to FFI functions,
etc.

Addresses issue #1529.

Also make sleep.c self-contained by moving initialization code,
instead of having part of the code in init.c, and add a header file
to accomodate this.
msec_sleep() now uses the usleep() implementation as well.

Fixes issues like #1532

They return None if no data available.

mpconfigport.h is a private, partial header not providing correct settings
unless included by py/mpconfig.h.

Scenario: module1 depends on some common file from lib/, so specifies it
in its SRC_MOD, and the same situation with module2, then common file
from lib/ eventually ends up listed twice in $(OBJ), which leads to link
errors.

Make is equipped to deal with such situation easily, quoting the manual:
"The value of $^ omits duplicate prerequisites, while $+ retains them and
preserves their order." So, just use $^ consistently in all link targets.

This is required to properly select among overloaded methods. It however
relies on java.lang.Object-overloaded method to come last, which appears
to be the case for OpenJDK.