common: Comment typo correction
Corrects the spelling of "functions".
This is more text than the actual diff.
BRANCH=none
TEST=none
@@ -513,7 +513,7 @@ void delay_sleep_by(uint32_t us);
/*
**
- * Funtctions to control deep sleep behavior. When disabled - the device never
+ * Functions to control deep sleep behavior. When disabled - the device never
* falls into deep sleep (the lowest power consumption state exit of which
* usually happens through the regular reset vector with just a few bits of
* state preserved).
