Clean up header includes

- Remove <errno.h> because related functions are in util.c now
 - Remove corresponding <string.h> if not used otherwise

components/temperature.c

@@ -16,9 +16,7 @@
 		return bprintf("%d", temp / 1000);
 	}
 #elif defined(__OpenBSD__)
-	#include <errno.h>
 	#include <stdio.h>
-	#include <string.h>
 	#include <sys/time.h> /* before <sys/sensors.h> for struct timeval */
 	#include <sys/sensors.h>
 	#include <sys/sysctl.h>