Make SOONG_HOST_OUT an alias for HOST_OUT

Soong now installs to the same directory as Make, point SOONG_HOST_OUT
at HOST_OUT.

Bug: 204136549
Test: m checkbuild
Change-Id: I49bfc0466056d270c8023288a6fe778c3445a900
diff --git a/CleanSpec.mk b/CleanSpec.mk
index dd5c476..957da92 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -769,6 +769,10 @@
 # More of SOONG_HOST_OUT_EXECUTABLES has been moved to HOST_OUT_EXECUTABLES
 $(call add-clean-step, rm -rf $(SOONG_HOST_OUT))
 
+# Last of SOONG_HOST_OUT_EXECUTABLES has been moved to HOST_OUT_EXECUTABLES
+# Don't use SOONG_HOST_OUT, it is now an alias for HOST_OUT.
+$(call add-clean-step, rm -rf $(OUT_DIR)/soong/host)
+
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************