Fix HOST_CROSS_OUT

Previously, HOST_CROSS_OUT was defined with the assumption that
windows_x86 is the only supported OS/Arch. In preparatio for Linux/ARM
support, HOST_CROSS_OUT is now defined using HOST_CROSS_OS and
HOST_CROSS_ARCH.

Bug: 159685774
Test: m

Change-Id: I0831c2885db37c44af4fd47bab8481bc885b4b7e
diff --git a/core/envsetup.mk b/core/envsetup.mk
index 167fed9..76e7dd3 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -328,7 +328,7 @@
 HOST_OUT := $(HOST_OUT_ROOT)/$(HOST_OS)-$(HOST_PREBUILT_ARCH)
 SOONG_HOST_OUT := $(SOONG_OUT_DIR)/host/$(HOST_OS)-$(HOST_PREBUILT_ARCH)
 
-HOST_CROSS_OUT := $(HOST_OUT_ROOT)/windows-$(HOST_PREBUILT_ARCH)
+HOST_CROSS_OUT := $(HOST_OUT_ROOT)/$(HOST_CROSS_OS)-$(HOST_CROSS_ARCH)
 
 .KATI_READONLY := HOST_OUT SOONG_HOST_OUT HOST_CROSS_OUT