s390: set bzImage as default image for packaging

Even though s390 compressed kernel support has been introduced long ago,
by default uncompressed kernel image is used by packaging targets like:
"make rpm-pkg", "make deb-pkg" as well as "make image_name".

At the same time "make install" would use compressed bzImage by default.
To avoid ambiguity, set bzImage as default image for packaging.
Signed-off-by: NVasily Gorbik <gor@linux.vnet.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Makefile

@@ -47,9 +47,6 @@ cflags-$(CONFIG_MARCH_Z14_TUNE)		+= -mtune=z14
 
 cflags-y += -Wa,-I$(srctree)/arch/$(ARCH)/include
 
-#KBUILD_IMAGE is necessary for make rpm
-KBUILD_IMAGE	:=arch/s390/boot/image
-
 #
 # Prevent tail-call optimizations, to get clearer backtraces:
 #
@@ -126,6 +123,9 @@ tools		:= arch/s390/tools
 
 all: image bzImage
 
+#KBUILD_IMAGE is necessary for packaging targets like rpm-pkg, deb-pkg...
+KBUILD_IMAGE	:= $(boot)/bzImage
+
 install: vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $@