Revert "Disable thinLTO for libhwbinder for riscv"

This reverts commit 0747671564e71304240aa7f2f2512466abe0695f.

The build no longer fails with ThinLTO, the workaround can be removed.

Test: presubmit
Bug: 254713216
Change-Id: I6144ecb5f5e8f465d4709bf0f90114ddc624fca8
diff --git a/Android.bp b/Android.bp
index d512152..81effa1 100644
--- a/Android.bp
+++ b/Android.bp
@@ -151,12 +151,4 @@
             },
         },
     },
-    arch: {
-        // TODO(b/254713216): undefined symbol in BufferedTextOutput::getBuffer
-        riscv64: {
-            lto: {
-                thin: false,
-            },
-        },
-    },
 }