Rename solana to solana-core (#5583)

core/benches/sigverify.rs

@@ -2,10 +2,10 @@
 
 extern crate test;
 
-use solana::packet::to_packets;
-use solana::recycler::Recycler;
-use solana::sigverify;
-use solana::test_tx::test_tx;
+use solana_core::packet::to_packets;
+use solana_core::recycler::Recycler;
+use solana_core::sigverify;
+use solana_core::test_tx::test_tx;
 use test::Bencher;
 
 #[bench]