Improve logging when we fail to load the native bridge implementation.

Test: boot
Bug: 130340935
Change-Id: I5e3b3cc92894e08408c79566a48458876d9bef53
diff --git a/libnativebridge/native_bridge.cc b/libnativebridge/native_bridge.cc
index e9b2a91..7600780 100644
--- a/libnativebridge/native_bridge.cc
+++ b/libnativebridge/native_bridge.cc
@@ -235,11 +235,16 @@
           } else {
             callbacks = nullptr;
             dlclose(handle);
-            ALOGW("Unsupported native bridge interface.");
+            ALOGW("Unsupported native bridge API in %s (is version %d not compatible with %d)",
+                  nb_library_filename, callbacks->version, NAMESPACE_VERSION);
           }
         } else {
           dlclose(handle);
+          ALOGW("Unsupported native bridge API in %s: %s not found",
+                nb_library_filename, kNativeBridgeInterfaceSymbol);
         }
+      } else {
+        ALOGW("Failed to load native bridge implementation: %s", dlerror());
       }
 
       // Two failure conditions: could not find library (dlopen failed), or could not find native