ARM: convert build of appended dtb zImage to list of dtbs

Allow CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE_NAMES to specify
a space separated list of dtbs to append to the zImage,
and name the resulting file zImage-dtb

Change-Id: I36d9108a2349bdbb373e95076dcb1417d8c7dce6
Signed-off-by: Colin Cross <ccross@android.com>
Git-commit: 6a3b63009b2fe3b025a88e8a0a5bcea145dda131
Git-repo: https://android.googlesource.com/kernel/common/
[mittals@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Shashank Mittal <mittals@codeaurora.org>
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0be6f11..b1dd350 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -266,6 +266,12 @@
 quiet_cmd_dtc = DTC     $@
 cmd_dtc = $(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 $(DTC_FLAGS) -d $(depfile) $<
 
+# cat
+# ---------------------------------------------------------------------------
+# Concatentate multiple files together
+quiet_cmd_cat = CAT     $@
+cmd_cat = (cat $(filter-out FORCE,$^) > $@) || (rm -f $@; false)
+
 # Bzip2
 # ---------------------------------------------------------------------------