Move from gcc to cc crate

gcc create has become deprecated: https://crates.io/crates/gcc

Signed-off-by: Fabio Utzig <utzig@apache.org>
diff --git a/sim/mcuboot-sys/Cargo.toml b/sim/mcuboot-sys/Cargo.toml
index 25d5652..09b323b 100644
--- a/sim/mcuboot-sys/Cargo.toml
+++ b/sim/mcuboot-sys/Cargo.toml
@@ -30,7 +30,7 @@
 enc-kw = []
 
 [build-dependencies]
-gcc = "0.3.54"
+cc = "1.0.25"
 
 [dependencies]
 lazy_static = "1.0"
diff --git a/sim/mcuboot-sys/build.rs b/sim/mcuboot-sys/build.rs
index 58b6569..4f98c71 100644
--- a/sim/mcuboot-sys/build.rs
+++ b/sim/mcuboot-sys/build.rs
@@ -1,6 +1,6 @@
 // Build mcuboot as a library, based on the requested features.
 
-extern crate gcc;
+extern crate cc;
 
 use std::env;
 use std::fs;
@@ -16,7 +16,7 @@
     let enc_rsa = env::var("CARGO_FEATURE_ENC_RSA").is_ok();
     let enc_kw = env::var("CARGO_FEATURE_ENC_KW").is_ok();
 
-    let mut conf = gcc::Build::new();
+    let mut conf = cc::Build::new();
     conf.define("__BOOTSIM__", None);
     conf.define("MCUBOOT_USE_FLASH_AREA_GET_SECTORS", None);
     conf.define("MCUBOOT_HAVE_ASSERT_H", None);