build: remove image prefix from kernel files in KDIR

This allows the image builder to change EXTRA_IMAGE_NAME at a later
point in time without breaking the build

Signed-off-by: Felix Fietkau <nbd@nbd.name>

include/image.mk

@@ -335,6 +335,7 @@ else
 endif
 
 define Device/Check
+  KDIR_KERNEL_IMAGE := $(KDIR)/$(1)$$(KERNEL_SUFFIX)
   _PROFILE_SET = $$(strip $$(foreach profile,$$(PROFILES) DEVICE_$(1),$$(call DEVICE_CHECK_PROFILE,$$(profile))))
   _TARGET := $$(if $$(_PROFILE_SET),install-images,install-disabled)
   ifndef IB
@@ -373,17 +374,17 @@ define Device/Build/compile
 endef
 
 define Device/Build/kernel
-  _KERNEL_IMAGES += $(KDIR)/$$(KERNEL_NAME)
+  _KERNEL_IMAGES += $$(KDIR_KERNEL_NAME)
   $(KDIR)/$$(KERNEL_NAME):: image_prepare
   $$(_TARGET): $$(if $$(KERNEL_INSTALL),$(BIN_DIR)/$$(KERNEL_IMAGE))
-  $(call Device/Export,$(KDIR)/$$(KERNEL_IMAGE),$(1))
-  $(BIN_DIR)/$$(KERNEL_IMAGE): $(KDIR)/$$(KERNEL_IMAGE)
+  $(call Device/Export,$$(KDIR_KERNEL_IMAGE),$(1))
+  $(BIN_DIR)/$$(KERNEL_IMAGE): $$(KDIR_KERNEL_IMAGE)
 	cp $$^ $$@
   ifndef IB
     ifdef CONFIG_IB
-      install: $(KDIR)/$$(KERNEL_IMAGE)
+      install: $$(KDIR_KERNEL_IMAGE)
     endif
-    $(KDIR)/$$(KERNEL_IMAGE): $(KDIR)/$$(KERNEL_NAME) $(CURDIR)/Makefile $$(KERNEL_DEPENDS)
+    $$(KDIR_KERNEL_IMAGE): $(KDIR)/$$(KERNEL_NAME) $(CURDIR)/Makefile $$(KERNEL_DEPENDS)
 	@rm -f $$@
 	$$(call concat_cmd,$$(KERNEL))
 	$$(if $$(KERNEL_SIZE),$$(call Device/Build/check_size,$$(KERNEL_SIZE)))
@@ -393,7 +394,7 @@ endef
 define Device/Build/image
   $$(_TARGET): $(BIN_DIR)/$(call IMAGE_NAME,$(1),$(2))
   $(eval $(call Device/Export,$(KDIR)/tmp/$(call IMAGE_NAME,$(1),$(2)),$(1)))
-  $(KDIR)/tmp/$(call IMAGE_NAME,$(1),$(2)): $(KDIR)/$$(KERNEL_IMAGE) $(KDIR)/root.$(1)$$(if $$(FS_OPTIONS/$(1)),+fs=$$(call param_mangle,$$(FS_OPTIONS/$(1))))
+  $(KDIR)/tmp/$(call IMAGE_NAME,$(1),$(2)): $$(KDIR_KERNEL_IMAGE) $(KDIR)/root.$(1)$$(if $$(FS_OPTIONS/$(1)),+fs=$$(call param_mangle,$$(FS_OPTIONS/$(1))))
 	@rm -f $$@
 	[ -f $$(word 1,$$^) -a -f $$(word 2,$$^) ]
 	$$(call concat_cmd,$(if $(IMAGE/$(2)/$(1)),$(IMAGE/$(2)/$(1)),$(IMAGE/$(2))))