Add debugging to ZipFileRO

Some assets are failing to read from ZIP files. This adds a bit more
debugging to figure out what's going on.

Change-Id: Id90e10546c54c85069a34478fbc28bc2523bda5d
diff --git a/libs/utils/ZipFileRO.cpp b/libs/utils/ZipFileRO.cpp
index 604f558..a0e01c6 100644
--- a/libs/utils/ZipFileRO.cpp
+++ b/libs/utils/ZipFileRO.cpp
@@ -508,8 +508,8 @@
         }
 
         if (get4LE(lfhBuf) != kLFHSignature) {
-            LOGW("didn't find signature at start of lfh, offset=%ld\n",
-                localHdrOffset);
+            LOGW("didn't find signature at start of lfh, offset=%ld (got 0x%08lx, expected 0x%08x)\n",
+                localHdrOffset, get4LE(lfhBuf), kLFHSignature);
             return false;
         }