Revert "editor: save and reset terminal after calling EDITOR"

This reverts commit 3d411afabc,
blindly opening /dev/tty and calling tcsetattr() seems to be causing
problems.

cf. https://bugs.eclipse.org/bugs/show_bug.cgi?id=577358
cf. https://lore.kernel.org/git/04ab7301-ea34-476c-eae4-4044fef74b91@gmail.com/

Signed-off-by: Junio C Hamano <gitster@pobox.com>

editor.c

@@ -3,7 +3,6 @@
 #include "strbuf.h"
 #include "run-command.h"
 #include "sigchain.h"
-#include "compat/terminal.h"
 
 #ifndef DEFAULT_EDITOR
 #define DEFAULT_EDITOR "vi"
@@ -51,8 +50,6 @@ const char *git_sequence_editor(void)
 static int launch_specified_editor(const char *editor, const char *path,
 				   struct strbuf *buffer, const char *const *env)
 {
-	int term_fail;
-
 	if (!editor)
 		return error("Terminal is dumb, but EDITOR unset");
 
@@ -86,10 +83,7 @@ static int launch_specified_editor(const char *editor, const char *path,
 		p.env = env;
 		p.use_shell = 1;
 		p.trace2_child_class = "editor";
-		term_fail = save_term(1);
 		if (start_command(&p) < 0) {
-			if (!term_fail)
-				restore_term();
 			strbuf_release(&realpath);
 			return error("unable to start editor '%s'", editor);
 		}
@@ -97,8 +91,6 @@ static int launch_specified_editor(const char *editor, const char *path,
 		sigchain_push(SIGINT, SIG_IGN);
 		sigchain_push(SIGQUIT, SIG_IGN);
 		ret = finish_command(&p);
-		if (!term_fail)
-			restore_term();
 		strbuf_release(&realpath);
 		sig = ret - 128;
 		sigchain_pop(SIGINT);