Relax cc dependency requirements.

Aleksei Sidorov · Aleksei Sidorov · commit 1e303e513d0a · 2019-03-28T14:38:26.000+03:00
diff --git a/Cargo.toml b/Cargo.toml
@@ -19,7 +19,7 @@ features = [ "rand", "serde" ]
 all-features = true
 
 [build-dependencies]
-cc = "=1.0.26"
+cc = "1.0"
 
 [lib]
 name = "secp256k1"
