Fix jobject_find() when a collision was removed

The search should proceed even if no entry was found in the bucket
array.

[GF-6968] libpbnjson: jobject_find() won't find a key after
 jobject_remove(another key with same hash)

Open-webOS-DCO-1.0-Signed-off-by: Anatolii Sakhnik <asakhnik@luxoft.com>

Change-Id: I8731699cecd5e067986ff351fd6e013d1fe5643f