LibreSSL 3.1 branch marked as stable; add support

.circleci/config.yml

@@ -298,10 +298,10 @@ workflows:
           library: libressl
           version: 2.5.5
       - linux:
-          name: x86_64-libressl-3.1.0
+          name: x86_64-libressl-3.1.1
           target: x86_64-unknown-linux-gnu
           library: libressl
-          version: 3.1.0
+          version: 3.1.1
       - macos:
           name: macos
       - macos:

openssl-sys/build/main.rs

@@ -217,6 +217,7 @@ See rust-openssl README for more information:
             (3, 0, 1) => ('3', '0', '1'),
             (3, 0, _) => ('3', '0', 'x'),
             (3, 1, 0) => ('3', '1', '0'),
+            (3, 1, _) => ('3', '1', 'x'),
             _ => version_error(),
         };
 
@@ -257,7 +258,7 @@ fn version_error() -> ! {
         "
 
 This crate is only compatible with OpenSSL 1.0.1 through 1.1.1, or LibreSSL 2.5
-through 3.0.x, but a different version of OpenSSL was found. The build is now aborting
+through 3.1.x, but a different version of OpenSSL was found. The build is now aborting
 due to this version mismatch.
 
 "