Rename soong.variable with target product

Bug: 277029044
Test: build succeeded and checked if out/soong/soong.variable has been
renamed

Change-Id: I035a52f3d8ad80d9e44a55e10fe537556ddecda8
diff --git a/core/soong_config.mk b/core/soong_config.mk
index 034d044..f18b8d2 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -1,5 +1,5 @@
 SOONG_MAKEVARS_MK := $(SOONG_OUT_DIR)/make_vars-$(TARGET_PRODUCT).mk
-SOONG_VARIABLES := $(SOONG_OUT_DIR)/soong.variables
+SOONG_VARIABLES := $(SOONG_OUT_DIR)/soong.$(TARGET_PRODUCT).variables
 SOONG_ANDROID_MK := $(SOONG_OUT_DIR)/Android-$(TARGET_PRODUCT).mk
 
 include $(BUILD_SYSTEM)/art_config.mk