use gmake on systems where it is available (OpenBSD)

giteapc/repos.py

@@ -138,8 +138,14 @@ class LocalRepo:
     # Make commands
 
     def make(self, target, env=None):
+        # Use GNU Make even on OpenBSD
+        if shutil.which("gmake") is not None:
+            command = "gmake"
+        else:
+            command = "make"
+
         with ChangeDirectory(self.folder):
-            return run(["make", "-f", "giteapc.make", target], env=env)
+            return run([command, "-f", "giteapc.make", target], env=env)
 
     def set_config(self, config):
         source = self.folder + f"/giteapc-config.make"