Increase 3B scratch buffers. (#1698)

The 128 MB was too optimistic.
Too bad it is not dynamically computed.

llama.cpp

@@ -63,7 +63,7 @@ static const size_t MB = 1024*1024;
 static const std::map<e_model, size_t> & MEM_REQ_SCRATCH0()
 {
     static std::map<e_model, size_t> k_sizes = {
-        { MODEL_3B,    128ull * MB },
+        { MODEL_3B,    256ull * MB },
         { MODEL_7B,    512ull * MB },
         { MODEL_13B,   512ull * MB },
         { MODEL_30B,   512ull * MB },
@@ -75,7 +75,7 @@ static const std::map<e_model, size_t> & MEM_REQ_SCRATCH0()
 static const std::map<e_model, size_t> & MEM_REQ_SCRATCH1()
 {
     static std::map<e_model, size_t> k_sizes = {
-        { MODEL_3B,    128ull * MB },
+        { MODEL_3B,    256ull * MB },
         { MODEL_7B,    512ull * MB },
         { MODEL_13B,   512ull * MB },
         { MODEL_30B,   512ull * MB },