bricks/stm32: Add umath alias for math module.

To be compatible with the `pybricks-api` we shouldn't have any modules
with the same name as the Python standard library. Most MicroPython
modules already have the "u" prefix, but `math` doesn't for some reason.

Author: dlech

CHANGELOG.md

@@ -10,6 +10,10 @@
   This makes resetting the angle optional, allowing to maintain absolute
   positioning for robots with gears ([support#389]).
 
+### Changed
+- Moved MicroPython `math` module to `umath` to be consistent with other
+  MicroPython modules.
+
 ### Fixed
 - Fixed City hub not always powering off on shutdown ([support#385]).
 

bricks/stm32/configport.h

@@ -121,7 +121,17 @@ extern const struct _mp_obj_module_t pb_package_pybricks;
 #define _PYBRICKS_PACKAGE_PYBRICKS \
     { MP_OBJ_NEW_QSTR(MP_QSTR_pybricks), (mp_obj_t)&pb_package_pybricks },
 
+// HACK: math is one of the few MicroPython modules that doesn't start with "u"
+// so we add an alias for it until it is fixed upstream
+#if MICROPY_PY_MATH
+#define _UMATH_MODULE \
+    { MP_ROM_QSTR(MP_QSTR_umath), MP_ROM_PTR(&mp_module_math) },
+#else
+#define _UMATH_MODULE
+#endif
+
 #define MICROPY_PORT_BUILTIN_MODULES \
+    _UMATH_MODULE                   \
     _PYBRICKS_PACKAGE_PYBRICKS      \