sync gettimeofday.2 with sys/time.h

[Dawe]

Index: gettimeofday.2
===================================================================
RCS file: /cvs/src/lib/libc/sys/gettimeofday.2,v
retrieving revision 1.24
diff -u -p -r1.24 gettimeofday.2
--- gettimeofday.2      17 Jul 2013 05:42:11 -0000      1.24
+++ gettimeofday.2      11 Sep 2013 13:18:50 -0000
@@ -77,7 +77,7 @@ are defined in
 as:
 .Bd -literal
 struct timeval {
-       long    tv_sec;         /* seconds since Jan. 1, 1970 */
+       time_t  tv_sec;         /* seconds since Jan. 1, 1970 */
        long    tv_usec;        /* and microseconds */
 };