Chibios: use WFI in idle. WIP suspend stuff.

keyboard/stm32_onekey/chconf.h

@@ -103,6 +103,10 @@
  */
 #define CH_CFG_NO_IDLE_THREAD               FALSE
 
+/* Use __WFI in the idle thread for waiting. Does lower the power
+ * consumption. */
+#define CORTEX_ENABLE_WFI_IDLE              TRUE
+
 /** @} */
 
 /*===========================================================================*/

keyboard/stm32_onekey/keymap_plain.c

@@ -25,7 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keymap.h"
 
 static const uint8_t keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
-    {{KC_A}},
+    {{KC_CAPS}}, // test with KC_CAPS, KC_A, KC_BTLD
 };
 
 static const uint16_t fn_actions[] = {