[POWERPC] Remove 'make zImage.dts' feature

Being able to selectively wrap a device tree with the zIimage at build
time has been deemed unnecessary, so this removes Makefile support for
that feature.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index fbafd96..187a39a 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -148,7 +148,7 @@
 
 CPPFLAGS_vmlinux.lds	:= -Upowerpc
 
-BOOT_TARGETS = zImage zImage.initrd zImage.dts zImage.dts_initrd uImage
+BOOT_TARGETS = zImage zImage.initrd uImage
 
 PHONY += $(BOOT_TARGETS)