Libunwindstack: Add -O0 to tools defaults on host

Extend the debug support from the host library to host tools.

Test: mmma system/core/libunwindstack
Change-Id: Ib6ea5f021d6b8139c545eaa2e6b1675befa4d3bd
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index 82f2e73..a6bf730 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -220,6 +220,15 @@
         "libbase",
         "liblzma",
     ],
+    target: {
+        // Always disable optimizations for host to make it easier to debug.
+        host: {
+            cflags: [
+                "-O0",
+                "-g",
+            ],
+        },
+    },
 }
 
 cc_binary {