dpdk: reduce value of DEFAULT_MBUF_POOL_SIZE to use it also as rx queue size

Author: TheSableCZ

input/dpdk.h

@@ -44,7 +44,7 @@ namespace ipxp {
 class DpdkOptParser : public OptionsParser {
 private:
     static constexpr size_t DEFAULT_MBUF_BURST_SIZE = 64;
-    static constexpr size_t DEFAULT_MBUF_POOL_SIZE = 16384;
+    static constexpr size_t DEFAULT_MBUF_POOL_SIZE = 4096;
     size_t pkt_buffer_size_;
     size_t pkt_mempool_size_;
     std::vector<uint16_t> port_numbers_;