maint: install: remove support for --preserve_context ("_", not "-")

* src/install.c: Its use has elicited a warning for two years.
Use --preserve-context instead.
* NEWS (changes in behavior): Mention this.

1 files changed, 3 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index 9a9b97a73..ceccaca44 100644
--- a/NEWS
+++ b/NEWS
@@ -47,6 +47,9 @@ GNU coreutils NEWS                                    -*- outline -*-
   df now aligns columns consistently, and no longer wraps entries
   with longer device identifiers, over two lines.
 
+  install now rejects its long-deprecated --preserve_context option.
+  Use --preserve-context instead.
+
   test now accepts "==" as a synonym for "="