Remove ndk_platform backend. Use the ndk backend.

The ndk_platform backend will soon be deprecated because the ndk backend
can serve the same purpose. This is to eliminate the confusion about
having two variants (ndk and ndk_platform) for the same 'ndk' backend.

Bug: 161456198
Test: m
Change-Id: I4498856a47896024698c53b3fc84e53959d639b8
diff --git a/Android.bp b/Android.bp
index 4a90312..9412b4b 100644
--- a/Android.bp
+++ b/Android.bp
@@ -22,7 +22,7 @@
         "libhidlbase",
         "libutils",
         "android.hardware.memtrack@1.0",
-        "android.hardware.memtrack-V1-ndk_platform",
+        "android.hardware.memtrack-V1-ndk",
     ],
     cflags: [
         "-Wall",