register description
| SLP_WAKEUP_INT_CLR | Clear sleep wakeup interrupt state |
| SLP_REJECT_INT_CLR | Clear sleep reject interrupt state |
| WDT_INT_CLR | Clear RTC WDT interrupt state |
| BROWN_OUT_INT_CLR | Clear brown out interrupt state |
| MAIN_TIMER_INT_CLR | Clear RTC main timer interrupt state |
| SWD_INT_CLR | Clear super watch dog interrupt state |
| BBPLL_CAL_INT_CLR | Need add desc |