Remove libc++demangle from static libs.

This is implicitly added by Soong with stl
https://cs.android.com/android/platform/superproject/+/master:build/soong/cc/stl.go;l=157;drc=cb0ac95bde896fa2aa59193a37ceb580758c322c

Test: m
Change-Id: Ie18a7cda8001deb3a0e714db02a50919e631c319

libc/malloc_debug/Android.bp

@@ -37,12 +37,6 @@ cc_library_static {
     },
     native_coverage: false,
 
-    target: {
-        android: {
-            static_libs: ["libc++demangle"],
-        },
-    },
-
     // -Wno-error=format-zero-length needed for gcc to compile.
     cflags: [
         "-Wall",