Merge #11971: fix man page; it's -OO not -O0

Patch by Lars Michelsen.
diff --git a/Misc/python.man b/Misc/python.man
index 2d15d5d..0921e4c 100644
--- a/Misc/python.man
+++ b/Misc/python.man
@@ -34,7 +34,7 @@
 .B \-O
 ]
 [
-.B \-O0
+.B \-OO
 ]
 [
 .B -Q
@@ -145,7 +145,7 @@
 .I .pyc
 to \fI.pyo\fP.  Given twice, causes docstrings to be discarded.
 .TP
-.B \-O0
+.B \-OO
 Discard docstrings in addition to the \fB-O\fP optimizations.
 .TP
 .B \-q