buzzer: fix simulator build, refactor sequence_length.

watch-library/shared/watch/watch_private_buzzer.c

@@ -23,6 +23,13 @@
  */
 #include "driver_init.h"
 
-// note: the buzzer uses a 1 MHz clock. these values were determined by dividing 1,000,000 by the target frequency.
-// i.e. for a 440 Hz tone (A4 on the piano), 1MHz/440Hz = 2273
-const uint16_t NotePeriods[108] = {18182,17161,16197,15288,14430,13620,12857,12134,11453,10811,10204,9631,9091,8581,8099,7645,7216,6811,6428,6068,5727,5405,5102,4816,4545,4290,4050,3822,3608,3405,3214,3034,2863,2703,2551,2408,2273,2145,2025,1911,1804,1703,1607,1517,1432,1351,1276,1204,1136,1073,1012,956,902,851,804,758,716,676,638,602,568,536,506,478,451,426,402,379,358,338,319,301,284,268,253,239,225,213,201,190,179,169,159,150,142,134,127};
+uint16_t sequence_length(int8_t *sequence) {
+    uint16_t result = 0;
+
+    while (*sequence != 0){
+        result += *(sequence + 1);
+        sequence += 2;
+    }
+
+    return result;
+}