imagebuilder: align filename with SDK

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

SVN-Revision: 44313

target/imagebuilder/Makefile

@@ -1,5 +1,5 @@
 # 
-# Copyright (C) 2006-2012 OpenWrt.org
+# Copyright (C) 2006-2015 OpenWrt.org
 #
 # This is free software, licensed under the GNU General Public License v2.
 # See /LICENSE for more information.
@@ -12,10 +12,7 @@ include $(INCLUDE_DIR)/version.mk
 
 override MAKEFLAGS=
 
-PKG_OS:=$(word 2,$(subst -, ,$(shell $(HOSTCC) -dumpmachine)))
-PKG_CPU:=$(word 1,$(subst -, ,$(shell $(HOSTCC) -dumpmachine)))
-
-IB_NAME:=OpenWrt-ImageBuilder-$(if $(CONFIG_VERSION_FILENAMES),$(VERSION_NUMBER)-)$(BOARD)$(if $(SUBTARGET),_$(SUBTARGET))-for-$(PKG_OS)-$(PKG_CPU)
+IB_NAME:=OpenWrt-ImageBuilder-$(if $(CONFIG_VERSION_FILENAMES),$(VERSION_NUMBER)-)$(BOARD)$(if $(SUBTARGET),-$(SUBTARGET)).$(HOST_OS)-$(HOST_ARCH)
 PKG_BUILD_DIR:=$(BUILD_DIR)/$(IB_NAME)
 IB_KDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(KERNEL_BUILD_DIR))
 IB_LDIR:=$(patsubst $(TOPDIR)/%,$(PKG_BUILD_DIR)/%,$(LINUX_DIR))