Default MK_META_MODE from MK_DIRDEPS_BUILD

This allows most of the build to simply consider MK_META_MODE

Update to latest dirdeps.mk so we can do:

make -f dirdeps.mk bin/cat.i386

Reviewed by:	bdrewery

share/mk/dirdeps.mk

@@ -1,5 +1,5 @@
 # $FreeBSD$
-# $Id: dirdeps.mk,v 1.54 2015/06/08 20:55:11 sjg Exp $
+# $Id: dirdeps.mk,v 1.55 2015/10/20 22:04:53 sjg Exp $
 
 # Copyright (c) 2010-2013, Juniper Networks, Inc.
 # All rights reserved.
@@ -243,6 +243,21 @@ DEP_${TARGET_SPEC_VARS:[$i]} := ${_tspec:[$i]}
 DEP_MACHINE := ${_DEP_TARGET_SPEC}
 .endif
 
+.if ${MAKEFILE:T} == ${.PARSEFILE} && empty(DIRDEPS) && ${.TARGETS:Uall:M*/*} != ""
+# This little trick let's us do
+#
+# mk -f dirdeps.mk some/dir.${TARGET_SPEC}
+#
+all:
+${.TARGETS:Nall}: all
+DIRDEPS := ${.TARGETS:M*/*}
+# so that -DNO_DIRDEPS works
+DEP_RELDIR := ${DIRDEPS:R:[1]}
+# disable DIRDEPS_CACHE as it does not like this trick
+MK_DIRDEPS_CACHE = no
+.endif
+
+
 # pickup customizations
 # as below you can use !target(_DIRDEP_USE) to protect things
 # which should only be done once.

share/mk/local.gendirdeps.mk

@@ -6,6 +6,7 @@ GENDIRDEPS_HEADER= echo '\# ${FreeBSD:L:@v@$$$v$$ @:M*F*}';
 # supress optional/auto dependecies
 # local.dirdeps.mk will put them in if necessary
 GENDIRDEPS_FILTER+= \
+	Nbin/cat.host \
 	Ngnu/lib/libssp/libssp_nonshared \
 	Ncddl/usr.bin/ctf* \
 	Nlib/clang/include \

share/mk/sys.mk

@@ -19,13 +19,12 @@ MACHINE_CPUARCH=${MACHINE_ARCH:C/mips(n32|64)?(el)?/mips/:C/arm(v6)?(eb|hf)?/arm
 
 # Some options we need now
 __DEFAULT_NO_OPTIONS= \
-	DIRDEPS_CACHE \
 	DIRDEPS_BUILD \
-	META_MODE \
-
+	DIRDEPS_CACHE
 
 __DEFAULT_DEPENDENT_OPTIONS= \
 	AUTO_OBJ/DIRDEPS_BUILD \
+	META_MODE/DIRDEPS_BUILD \
 	STAGING/DIRDEPS_BUILD \
 	SYSROOT/DIRDEPS_BUILD