ensure that IMAGEDIR exists (thus globbable)

It appears that manually specified IMAGEDIR, e.g. by adding

  IMAGEDIR = ~/out/$(shell date +%Y%m%d)

to ~/.mkimage/profiles.mk, might be problematic due to
missing globbing.  Let's make sure the paths are globbed
and directories are created -- since make's wildcard()
returns an empty string when there's nothing there [yet].

image.in/Makefile

@@ -29,8 +29,11 @@ $(info warning: mkimage-$(MKI_VERSION) is suboptimal, consider upgrading)
 $(warning consider upgrading mkimage to $(MKI_VER_OPTIMAL) or better)
 endif
 
+# glob it just in case
+IMAGEDIR := $(wildcard $(IMAGEDIR))
+
 # additional means to reduce havoc in IMAGEDIR
-IMAGE_SORTDIR := $(SORTDIR)
+IMAGE_SORTDIR := $(wildcard $(SORTDIR))
 
 # reconstruct instead of passing yet another variable
 IMAGE_OUTDIR   := $(IMAGEDIR)$(IMAGE_SORTDIR:%=/%)

lib/build.mk

@@ -42,7 +42,7 @@ IMAGEDIR ?= $(shell \
 	fi; \
 )
 
-LOGDIR ?= $(IMAGEDIR)
+LOGDIR ?= $(wildcard $(IMAGEDIR))
 
 # actual build starter
 # NB: our output MUST go into stderr to escape POSTPROC

lib/profile.mk

@@ -82,8 +82,8 @@ profile/bare: profile/init
 	} >&2
 	@$(call try,MKIMAGE_PREFIX,/usr/share/mkimage)
 	@$(call try,GLOBAL_VERBOSE,)
-	@$(call try,IMAGEDIR,$(IMAGEDIR))
-	@$(call try,LOGDIR,$(LOGDIR))
+	@$(call try,IMAGEDIR,$(wildcard $(IMAGEDIR)))
+	@$(call try,LOGDIR,$(wildcard $(LOGDIR)))
 	@$(call try,BRANDING,altlinux-sisyphus)
 ifeq (,$(REPO:altlinux%=))
 	@$(call set,IMAGE_INIT_LIST,+branding-$$(BRANDING)-release)

main.mk

@@ -34,6 +34,12 @@ include $(sort $(wildcard lib/*.mk))
 include conf.d/*.mk
 include features.in/*/config.mk
 
+# ensure the outdir is created and globbable
+ifdef IMAGEDIR
+$(shell mkdir -p $(IMAGEDIR))
+IMAGEDIR := $(wildcard $(IMAGEDIR))
+endif
+
 # FIXME: this is buggy since *.mk can expose parts conditionally
 #        (e.g. test.mk does DEBUG-only bits) and these will fail
 DISTRO_TARGETS := $(shell sed -n 's,^\(distro/[^:.]\+\):.*$$,\1,p' \