image: fix image generation within ImageBuilder

Changes introduced in commit d604a07225c5 ("build: add CycloneDX SBOM
JSON support") broke ImageBuilder:

  Cannot open '/openwrt-imagebuilder-ath79-generic.Linux-x86_64/tmp/.packageinfo': No such file or directory

So lets fix it by wrapping the BOM generation behind condition of IB
feature check.

Fixes: #13881
Fixes: d604a07225c5 ("build: add CycloneDX SBOM JSON support")
Signed-off-by: Petr Štetiar <[email protected]>

include/image.mk

@@ -277,11 +277,13 @@ endef
 define Image/Manifest
 	$(call opkg,$(TARGET_DIR_ORIG)) list-installed > \
 		$(BIN_DIR)/$(IMG_PREFIX)$(if $(PROFILE_SANITIZED),-$(PROFILE_SANITIZED)).manifest
+ifndef IB
 	$(if $(CONFIG_JSON_CYCLONEDX_SBOM), \
 		$(SCRIPT_DIR)/package-metadata.pl imgcyclonedxsbom \
 		$(TMP_DIR)/.packageinfo \
 		$(BIN_DIR)/$(IMG_PREFIX)$(if $(PROFILE_SANITIZED),-$(PROFILE_SANITIZED)).manifest > \
 		$(BIN_DIR)/$(IMG_PREFIX)$(if $(PROFILE_SANITIZED),-$(PROFILE_SANITIZED)).bom.cdx.json)
+endif
 endef
 
 define Image/gzip-ext4-padded-squashfs