Replace http://man7.org links with https://man7.org links.

I suspect the way http:// dies is that browsers just interpret it as
https:// anyway, but there's no reason not to just bulk fix all these at
source.

Change-Id: I38fa91728846d7c33207ef1bdadd4910eac9e941
diff --git a/libc/stdio/fmemopen.cpp b/libc/stdio/fmemopen.cpp
index 6e333ba..c58fca9 100644
--- a/libc/stdio/fmemopen.cpp
+++ b/libc/stdio/fmemopen.cpp
@@ -34,7 +34,7 @@
 #include "local.h"
 
 // See http://pubs.opengroup.org/onlinepubs/9699919799/functions/fmemopen.html
-// and http://man7.org/linux/man-pages/man3/fmemopen.3.html for documentation.
+// and https://man7.org/linux/man-pages/man3/fmemopen.3.html for documentation.
 
 struct fmemopen_cookie {
   char* buf;