Switch libvndksupport's linker.c to C++

Bug: none
Test: device boots
Change-Id: I64237006a7f903647c8d8f7ca681b1da23ac53a9
diff --git a/libvndksupport/Android.bp b/libvndksupport/Android.bp
index e5b536c..f4544a1 100644
--- a/libvndksupport/Android.bp
+++ b/libvndksupport/Android.bp
@@ -3,7 +3,7 @@
 cc_library {
     name: "libvndksupport",
     native_bridge_supported: true,
-    srcs: ["linker.c"],
+    srcs: ["linker.cpp"],
     cflags: [
         "-Wall",
         "-Werror",