Revert "fix build"

This reverts commit fb76b2b3abfe08af1f0d41b537fe10fc80a2ed07.
diff --git a/products/cyanogen_vega.mk b/products/cyanogen_vega.mk
index 76144b3..031e4e9 100644
--- a/products/cyanogen_vega.mk
+++ b/products/cyanogen_vega.mk
@@ -1,7 +1,7 @@
 $(call inherit-product, device/advent/vega/vega.mk)
 
 # skips themes and keeps the resulting rom tiny so it fits on /system/ with all languages included
-PRODUCT_SPECIFIC_DEFINES += SKIP_THEMES=true
+SKIP_THEMES := true
 
 # Inherit some common cyanogenmod stuff.
 $(call inherit-product, vendor/cyanogen/products/common_full.mk)