ChibiOS 21.11.1 update. (#16251)

* ChibiOS 21.11.1 update.

* `uf2-tinyuf2` => `tinyuf2`

* Updated chibios-contrib, fixup preprocessor for tinyuf2 bootloader.

* Fixup keychron L433 boards.

* Makefile cleanup.

* RISC-V build fixes.

* Fixup RISC-V build.

platforms/chibios/wait.c

@@ -31,7 +31,7 @@ void wait_us(uint16_t duration) {
      * Only use this timer on the main thread;
      * other threads need to use their own timer.
      */
-    if (chThdGetSelfX() == &ch.mainthread && duration < (1ULL << (sizeof(gptcnt_t) * 8))) {
+    if (chThdGetSelfX() == &(currcore->mainthread) && duration < (1ULL << (sizeof(gptcnt_t) * 8))) {
         gptStart(&WAIT_US_TIMER, &gpt_cfg);
         gptPolledDelay(&WAIT_US_TIMER, duration);
     } else {