mksh: Remove defer-always flag from printf.

Previously this deferred to a printf binary if one was found in $PATH, which
completely defeats the point of using the builtin for performance reasons.  We
always create a printf wrapper so one was always found.  A nasty side-effect of
this was that with TOOLS_PLATFORM.printf=printf we would end up in a recursive
loop.

Now printf will always use the builtin.  Bump PKGREVISION.

shells/mksh/Makefile

@@ -1,8 +1,8 @@
-# $NetBSD: Makefile,v 1.45 2022/12/19 13:42:34 jperkin Exp $
+# $NetBSD: Makefile,v 1.46 2023/05/04 10:15:53 jperkin Exp $
 
 DISTNAME=		mksh-R59b
 PKGNAME=		${DISTNAME:S/-R/-/}
-PKGREVISION=		3
+PKGREVISION=		4
 CATEGORIES=		shells
 MASTER_SITES=		# maintained locally
 DISTFILES=		# empty

shells/mksh/files/funcs.c

@@ -156,7 +156,7 @@ const struct builtin mkshbuiltins[] = {
 	{"mknod", c_mknod},
 #endif
 #ifdef MKSH_PRINTF_BUILTIN
-	{"~printf", c_printf},
+	{"printf", c_printf},
 #endif
 #if HAVE_SELECT
 	{"sleep", c_sleep},