Enable building guest Gfxstream components on host

... so that upcoming end2end tests can use the GL/VK ICDs.

Bug: b/292257025
Test: mma
Change-Id: I8f3a19a6f8f81b2f368b4a1d5031d9e77358e327
diff --git a/guest/gralloc_cb/Android.bp b/guest/gralloc_cb/Android.bp
index ff8e9bb..9565d00 100644
--- a/guest/gralloc_cb/Android.bp
+++ b/guest/gralloc_cb/Android.bp
@@ -21,6 +21,7 @@
 
 cc_library_headers {
     name: "libgralloc_cb.ranchu",
+    host_supported: true,
     vendor_available: true,
     export_include_dirs: ["include"],
     header_libs: [