Merge branch 'cb/add-p-single-key-fix'

The single-key-input mode in "git add -p" had some code to handle
keys that generate a sequence of input via ReadKey(), which did not
handle end-of-file correctly, which has been fixed.

* cb/add-p-single-key-fix:
  add -p: avoid use of undefined $key when ReadKey -> EOF

git-add--interactive.perl

@@ -1175,6 +1175,7 @@ sub prompt_single_character {
 		ReadMode 'cbreak';
 		my $key = ReadKey 0;
 		ReadMode 'restore';
+		if (defined $key) {
 			if ($use_termcap and $key eq "\e") {
 				while (!defined $term_escapes{$key}) {
 					my $next = ReadKey 0.5;
@@ -1183,7 +1184,8 @@ sub prompt_single_character {
 				}
 				$key =~ s/\e/^[/;
 			}
-		print "$key" if defined $key;
+			print "$key";
+		}
 		print "\n";
 		return $key;
 	} else {