s390: remove uncompressed kernel image build

Dropping support for uncompressed kernel "image" build. Having
both image and bzImage makes it complicated to add new code to an
early boot phase (which is part of vmlinux for uncompressed kernel and
a separate arch/s390/boot/compressed/vmlinux for bzImage).

e.g. sclp_early_core.o is used for both, the decompressor phase and the
main kernel. The fact of having uncompressed kernel "image" forces us
to have a single object file and sacrifice instrumentation flags on such
files (so that we could use them early). The story gets much more
complicated with the need to utilize some of the string functions.

With bzImage only support, we have 2 separate boot stages each built
and linked separately, which allows to reuse some shared code, but
recompile with appropriate flags.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/Makefile

@@ -129,7 +129,7 @@ boot		:= arch/s390/boot
 syscalls	:= arch/s390/kernel/syscalls
 tools		:= arch/s390/tools
 
-all: image bzImage
+all: bzImage
 
 #KBUILD_IMAGE is necessary for packaging targets like rpm-pkg, deb-pkg...
 KBUILD_IMAGE	:= $(boot)/bzImage
@@ -137,7 +137,7 @@ KBUILD_IMAGE	:= $(boot)/bzImage
 install: vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $@
 
-image bzImage: vmlinux
+bzImage: vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 
 zfcpdump:
@@ -160,8 +160,7 @@ archprepare:
 
 # Don't use tabs in echo arguments
 define archhelp
-  echo  '* image           - Kernel image for IPL ($(boot)/image)'
-  echo	'* bzImage         - Compressed kernel image for IPL ($(boot)/bzImage)'
+  echo	'* bzImage         - Kernel image for IPL ($(boot)/bzImage)'
   echo	'  install         - Install kernel using'
   echo	'                    (your) ~/bin/$(INSTALLKERNEL) or'
   echo	'                    (distribution) /sbin/$(INSTALLKERNEL) or'

arch/s390/boot/Makefile

@@ -3,13 +3,9 @@
 # Makefile for the linux s390-specific parts of the memory manager.
 #
 
-targets := image
-targets += bzImage
+targets := bzImage
 subdir- := compressed
 
-$(obj)/image: vmlinux FORCE
-	$(call if_changed,objcopy)
-
 $(obj)/bzImage: $(obj)/compressed/vmlinux FORCE
 	$(call if_changed,objcopy)