shared/timeutils: Remove useless void-return.

The C99 standard states:

    6.8.6.4 The return statement Constraints

    A return statement with an expression shall not appear in a function
    whose return type is void.  A return statement without an expression
    shall only appear in a function whose return type is void.

And when `-pedantic` is enabled the compiler gives an error.

Signed-off-by: Yoctopuce <dev@yoctopuce.com>

shared/timeutils/timeutils.h

@@ -60,7 +60,7 @@ mp_uint_t timeutils_mktime_2000(mp_uint_t year, mp_int_t month, mp_int_t mday,
 
 static inline void timeutils_seconds_since_epoch_to_struct_time(uint64_t t, timeutils_struct_time_t *tm) {
     // TODO this will give incorrect results for dates before 2000/1/1
-    return timeutils_seconds_since_2000_to_struct_time(t - TIMEUTILS_SECONDS_1970_TO_2000, tm);
+    timeutils_seconds_since_2000_to_struct_time(t - TIMEUTILS_SECONDS_1970_TO_2000, tm);
 }
 
 static inline uint64_t timeutils_mktime(mp_uint_t year, mp_int_t month, mp_int_t mday, mp_int_t hours, mp_int_t minutes, mp_int_t seconds) {