patch 8.1.2243: typos in comments

Problem:    Typos in comments.
Solution:   Fix the typos. (Dominique Pelle, closes #5160)  Also adjust
            formatting a bit.
diff --git a/src/pty.c b/src/pty.c
index a2162e2..86fbca2 100644
--- a/src/pty.c
+++ b/src/pty.c
@@ -15,7 +15,7 @@
  * The parts that are not used in Vim have been deleted.
  * See the "screen" sources for the complete stuff.
  *
- * This specific version is distibuted under the Vim license (attribution by
+ * This specific version is distributed under the Vim license (attribution by
  * Juergen Weigert), the GPL applies to the original version, see the
  * copyright notice below.
  */