Add LinuxBionic OsType

Actual support will come in later changes.

Bug: 31559095
Test: out/soong/build.ninja is identical
Change-Id: I31392fb78a51f43567d16aef89e32cd5137cdbc1
diff --git a/Android.bp b/Android.bp
index 9324020..66702b1 100644
--- a/Android.bp
+++ b/Android.bp
@@ -187,6 +187,23 @@
 }
 
 //
+// Defaults to enable various configurations of host bionic
+//
+
+cc_defaults {
+    name: "linux_bionic_supported",
+    host_supported: true,
+    target: {
+        host: {
+            enabled: false,
+        },
+        linux_bionic: {
+            enabled: true,
+        },
+    },
+}
+
+//
 // C static libraries extracted from the gcc toolchain
 //