correct Research Unix edition "appeared in" use in HISTORY

Starting from "Combined Table of Contents" in Doug McIlroy's
"A Research UNIX Reader" a table of which edition manuals appeared in.
Checked against manuals from bitsavers/TUHS and source from TUHS where
available.

Ingo points out there are cases where something is included but not
documented until a later release.
bcd(6)		v6	v7
printf(3)	v2	v4
abort(3)	v5	v6
system(3)	v6	v7
fmod(3)		v5	v6

ok schwarze@

1 files changed, 3 insertions, 3 deletions

diff --git a/src/lib/libc/stdlib/qsort.3 b/src/lib/libc/stdlib/qsort.3
index de3e58fc23..4c0cddaccb 100644
--- a/src/lib/libc/stdlib/qsort.3
+++ b/src/lib/libc/stdlib/qsort.3
@@ -29,9 +29,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: qsort.3,v 1.26 2019/05/15 16:58:56 schwarze Exp $
+.\"     $OpenBSD: qsort.3,v 1.27 2020/02/08 01:09:57 jsg Exp $
 .\"
-.Dd $Mdocdate: May 15 2019 $
+.Dd $Mdocdate: February 8 2020 $
 .Dt QSORT 3
 .Os
 .Sh NAME
@@ -273,4 +273,4 @@ function conforms to
 A
 .Fn qsort
 function first appeared in
-.At v3 .
+.At v2 .