19706: boards/olimex-msp430-h2618: add new board r=maribu a=maribu
### Contribution description
This adds support of the Olimex MSP430-H2618 board. This board has plenty of RAM and ROM for an MSP430 board (even more than the z1), but still is easily obtainable.
Co-authored-by: Marian Buschsieweke <marian.buschsieweke@ovgu.de>
Co-authored-by: Marian Buschsieweke <marian.buschsieweke@posteo.net>
19695: drivers/hih6130: avoid using floats r=maribu a=maribu
### Contribution description
- avoid using floating point arithmetic
- use ztimer instead of xtimer
- use fmt to print fixed point numbers in the test app
Co-authored-by: Marian Buschsieweke <marian.buschsieweke@posteo.net>
19585: tests: move leftover sys related tests to test/sys + move tests/sys/candev to tests/drivers r=aabadie a=aabadie
19586: tests: move net related applications to test/net r=aabadie a=aabadie
Co-authored-by: Alexandre Abadie <alexandre.abadie@inria.fr>
