Restore Peter's version of static __sF. There's too much pain for it

to be static for 5.0.  I may remove this for 5.1 or 5.2.  No more
binaries or libarires will be generated with __sF starting as of
yesterday.  Originally the plan had been to eliminate this for 5.0,
but we didn't get the __std{in,out,err}p changes merged into -stable
until yesterday (rather than in September 2001 like it should have
been).  Given that didn't happen on time, we can't do the other part
of the scheme now.

# Please do not change this without talking to me first.

lib/libc/stdio/findfp.c

@@ -69,7 +69,10 @@ static struct glue uglue = { NULL, FOPEN_MAX - 3, usual };
 
 static struct __sFILEX __sFX[3];
 
-static FILE __sF[3] = {
+#if LIBC_MAJOR >= 6
+static
+#endif
+FILE __sF[3] = {
 	std(__SRD, STDIN_FILENO),
 	std(__SWR, STDOUT_FILENO),
 	std(__SWR|__SNBF, STDERR_FILENO)