Support exporting device arch toolchain info

Test: bp2build.sh
Bug: 187084665
Change-Id: I49e75f603accab519784dbaf25d85db0010587a3
diff --git a/cc/config/arm_device.go b/cc/config/arm_device.go
index b5afe40..0fe5e68 100644
--- a/cc/config/arm_device.go
+++ b/cc/config/arm_device.go
@@ -188,6 +188,9 @@
 	exportStringListStaticVariable("ArmArmCflags", armArmCflags)
 	exportStringListStaticVariable("ArmThumbCflags", armThumbCflags)
 
+	exportedStringListDictVars.Set("ArmArchVariantCflags", armArchVariantCflags)
+	exportedStringListDictVars.Set("ArmCpuVariantCflags", armCpuVariantCflags)
+
 	// Clang arch variant cflags
 	exportStringListStaticVariable("ArmArmv7ACflags", armArchVariantCflags["armv7-a"])
 	exportStringListStaticVariable("ArmArmv7ANeonCflags", armArchVariantCflags["armv7-a-neon"])