omni: Replace ADDITIONAL_BUILD_PROPERTIES

vendor/omni/build/fingerprint.mk:3: error: ADDITIONAL_BUILD_PROPERTIES is obsolete.  Please use ADDITIONAL_SYSTEM_PROPERTIES.

Change-Id: I5396f60c741b480182bbbf047c1c1f0a911a028b
diff --git a/build/fingerprint.mk b/build/fingerprint.mk
index 69256cd..f9b8349 100644
--- a/build/fingerprint.mk
+++ b/build/fingerprint.mk
@@ -1,5 +1,5 @@
 # Build fingerprint
 ifneq ($(BUILD_FINGERPRINT),)
-ADDITIONAL_BUILD_PROPERTIES += \
+ADDITIONAL_SYSTEM_PROPERTIES += \
     ro.build.fingerprint=$(BUILD_FINGERPRINT)
 endif