UBUNTU: SAUCE: Add vmlinux.strip to BOOT_TARGETS1

This came in via "UBUNTU: Rebase to v4.2-rc3", but I'm not
sure why.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

arch/powerpc/Makefile

@@ -241,7 +241,7 @@ drivers-$(CONFIG_OPROFILE)	+= arch/powerpc/oprofile/
 all: zImage
 
 # With make 3.82 we cannot mix normal and wildcard targets
-BOOT_TARGETS1 := zImage zImage.initrd uImage
+BOOT_TARGETS1 := zImage zImage.initrd uImage vmlinux.strip
 BOOT_TARGETS2 := zImage% dtbImage% treeImage.% cuImage.% simpleImage.% uImage.%
 
 PHONY += $(BOOT_TARGETS1) $(BOOT_TARGETS2)