sysdev: revert changes to can retrieve microseconds, but fix compilation

The change was made in 20233596
It was just a missing header, and i changed all the code.

psys/src/sysdevs.c

 #define SYSDEVS_G
 
 #include <time.h>
+#include <sys/time.h>
   
 #include <p2c/p2c.h>
 #include <p2c/sysglobals.h>
@@ -8,11 +9,11 @@
 
 long sysclock()
 {
-	time_t t = time(NULL);
-	struct tm *tz;
-	tz = localtime(&t);
+	struct timeval tv;
+	struct timezone tz;
 
-	return(tz->tm_sec % 86400 * 100 /*+ tz->tv_usec / 10000*/);
+	gettimeofday(&tv, &tz);
+	return tv.tv_sec % 86400 * 100 + tv.tv_usec / 10000;
 }
 
 
@@ -29,14 +30,18 @@ void sysdate(daterec *thedate)
 
 void systime(timerec *thetime)
 {
+	struct timeval tv;
+	struct timezone tz;
 	struct tm *t;
 	time_t temp;
 
-	temp = time(NULL);
+	gettimeofday(&tv, &tz);
+	temp = tv.tv_sec;
 	t = localtime(&temp);
+
 	thetime->hour = t->tm_hour;
 	thetime->minute = t->tm_min;
-	thetime->centisecond = t->tm_sec*100 /*+ time.tv_usec/10000*/;
+	thetime->centisecond = t->tm_sec * 100 + tv.tv_usec / 10000;
 }
 
 void SETRUNLIGHT(int c)