Kbuild: arch: look for generated headers in obtree

There are very few files that need add an -I$(obj) gcc for the preprocessor
or the assembler. For C files, we add always these for both the objtree and
srctree, but for the other ones we require the Makefile to add them, and
Kbuild then adds it for both trees.

As a preparation for changing the meaning of the -I$(obj) directive to
only refer to the srctree, this changes the two instances in arch/x86 to use
an explictit $(objtree) prefix where needed, otherwise we won't find the
headers any more, as reported by the kbuild 0day builder.

arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory

Signed-off-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Michal Marek <[e-mail]>

arch/alpha/boot/Makefile

···
 OBJSTRIP	:= $(obj)/tools/objstrip
 
 HOSTCFLAGS	:= -Wall -I$(objtree)/usr/include
-BOOTCFLAGS	+= -I$(obj) -I$(srctree)/$(obj)
+BOOTCFLAGS	+= -I$(objtree)/$(obj) -I$(srctree)/$(obj)
 
 # SRM bootable image.  Copy to offset 512 of a partition.
 $(obj)/bootimage: $(addprefix $(obj)/tools/,mkbb lxboot bootlx) $(obj)/vmlinux.nh

arch/powerpc/boot/Makefile

···
 BOOTCFLAGS	+= -fno-stack-protector
 endif
 
-BOOTCFLAGS	+= -I$(obj) -I$(srctree)/$(obj)
+BOOTCFLAGS	+= -I$(objtree)/$(obj) -I$(srctree)/$(obj)
 
 DTC_FLAGS	?= -p 1024
 

arch/powerpc/kvm/Makefile

···
 obj-$(CONFIG_KVM_EXIT_TIMING) += timing.o
 obj-$(CONFIG_KVM_BOOK3S_HANDLER) += book3s_exports.o
 
-AFLAGS_booke_interrupts.o := -I$(obj)
+AFLAGS_booke_interrupts.o := -I$(objtree)/$(obj)
 
 kvm-e500-objs := \
 	$(common-objs-y) \

arch/s390/boot/compressed/Makefile

···
 $(obj)/sizes.h: vmlinux
 	$(call if_changed,sizes)
 
-AFLAGS_head.o += -I$(obj)
+AFLAGS_head.o += -I$(objtree)/$(obj)
 $(obj)/head.o: $(obj)/sizes.h
 
-CFLAGS_misc.o += -I$(obj)
+CFLAGS_misc.o += -I$(objtree)/$(obj)
 $(obj)/misc.o: $(obj)/sizes.h
 
 OBJCOPYFLAGS_vmlinux.bin :=  -R .comment -S

arch/um/Makefile

···
 
 KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
 		   -I$(srctree)/$(HOST_DIR)/include/uapi \
-		   -I$(HOST_DIR)/include/generated \
-		   -I$(HOST_DIR)/include/generated/uapi
+		   -I$(objtree)/$(HOST_DIR)/include/generated \
+		   -I$(objtree)/$(HOST_DIR)/include/generated/uapi
 
 # -Derrno=kernel_errno - This turns all kernel references to errno into
 # kernel_errno to separate them from the libc errno.  This allows -fno-common

arch/x86/boot/Makefile

···
 	$(call if_changed,zoffset)
 
 
-AFLAGS_header.o += -I$(obj)
+AFLAGS_header.o += -I$(objtree)/$(obj)
 $(obj)/header.o: $(obj)/zoffset.h
 
 LDFLAGS_setup.elf	:= -T

arch/x86/realmode/rm/Makefile

···
 $(obj)/realmode.lds: $(obj)/pasyms.h
 
 LDFLAGS_realmode.elf := --emit-relocs -T
-CPPFLAGS_realmode.lds += -P -C -I$(obj)
+CPPFLAGS_realmode.lds += -P -C -I$(objtree)/$(obj)
 
 targets += realmode.elf
 $(obj)/realmode.elf: $(obj)/realmode.lds $(REALMODE_OBJS) FORCE