Add version info (date) to root fs image

package/Makefile.in

@@ -63,7 +63,7 @@ TOOL_BUILD_DIR=$(BASE_DIR)/$(TOPDIR_PREFIX)toolchain_build_$(ARCH)$(ARCH_FPU_SUF
 
 # Quotes are needed for spaces et al in path components.
 TARGET_PATH="$(TOOL_BUILD_DIR)/bin:$(STAGING_DIR)/bin:$(STAGING_DIR)/usr/bin:$(PATH)"
-IMAGE:=$(BINARIES_DIR)/rootfs.$(ARCH)$(ARCH_FPU_SUFFIX)
+IMAGE:=$(BINARIES_DIR)/rootfs.$(ARCH)$(ARCH_FPU_SUFFIX)-$(DATE)
 GNU_TARGET_NAME=$(OPTIMIZE_FOR_CPU)-linux
 REAL_GNU_TARGET_NAME=$(OPTIMIZE_FOR_CPU)$(GNU_TARGET_SUFFIX)
 TARGET_CROSS=$(STAGING_DIR)/usr/bin/$(REAL_GNU_TARGET_NAME)-
@@ -75,7 +75,7 @@ TOOLCHAIN_EXTERNAL_PATH:=$(strip $(subst ",, $(BR2_TOOLCHAIN_EXTERNAL_PATH)))
 #"))
 TOOL_BUILD_DIR=$(BASE_DIR)/$(TOPDIR_PREFIX)toolchain_build_$(TOOLCHAIN_EXTERNAL_PREFIX)
 TARGET_PATH="$(STAGING_DIR)/bin:$(TOOL_BUILD_DIR)/bin:$(TOOLCHAIN_EXTERNAL_PATH)/bin:$(PATH)"
-IMAGE:=$(BINARIES_DIR)/rootfs.$(TOOLCHAIN_EXTERNAL_PREFIX)
+IMAGE:=$(BINARIES_DIR)/rootfs.$(TOOLCHAIN_EXTERNAL_PREFIX)-$(DATE)
 
 REAL_GNU_TARGET_NAME=$(TOOLCHAIN_EXTERNAL_PREFIX)
 GNU_TARGET_NAME=$(TOOLCHAIN_EXTERNAL_PREFIX)