fix some manpage cross references

sys/man/1/pkg

@@ -115,7 +115,6 @@ source files of packages installed locally.
 .br
 .B http://plan9.bell-labs.com/sources/contrib/staal1978/pkg
 .SH SEE ALSO
-.IR contrib (1) ,
 .IR gzip (1) ,
 .IR tar (1)
 .SH HISTORY

sys/man/1/vnc

@@ -197,8 +197,6 @@ print verbose output to standard error.
 .SH SOURCE
 .B /sys/src/cmd/vnc
 .SH "SEE ALSO
-.IR drawterm (8)
-.br
 .B http://www.uk.research.att.com/vnc
 .SH BUGS
 If the remote frame buffer is larger than the local screen,

sys/man/4/iostats

@@ -61,7 +61,7 @@ The
 .B -C
 flag sets the MCACHE flag on the mount which allows
 the kernel to cache (see 
-.IR bind(1) ).
+.IR bind (1)).
 .SH EXAMPLE
 Display summary of file I/O incurred by
 .IR ls (1):