tweaks: remove a superfluous global variable

There were no calls of statusbar() or statusline() before curses mode
was entered.  But since the previous commit curses mode is entered
even earlier, so...

src/global.c

@@ -45,8 +45,6 @@ bool mute_modifiers = FALSE;
 bool bracketed_paste = FALSE;
 		/* Whether text is being pasted into nano from outside. */
 
-bool started_curses = FALSE;
-		/* Becomes TRUE when curses mode has been entered the first time. */
 bool we_are_running = FALSE;
 		/* Becomes TRUE as soon as all options and files have been read. */
 bool more_than_one = FALSE;

src/nano.c

@@ -2045,8 +2045,6 @@ int main(int argc, char **argv)
 	if (initscr() == NULL)
 		exit(1);
 
-	started_curses = TRUE;
-
 #ifdef ENABLE_COLOR
 	/* If the terminal can do colors, tell ncurses to switch them on. */
 	if (has_colors())

src/proto.h

@@ -34,7 +34,6 @@ extern bool shift_held;
 extern bool mute_modifiers;
 extern bool bracketed_paste;
 
-extern bool started_curses;
 extern bool we_are_running;
 extern bool more_than_one;
 

src/winio.c

@@ -2150,7 +2150,7 @@ void statusline(message_type importance, const char *msg, ...)
 
 #ifndef NANO_TINY
 	/* Curses mode shouldn't be off when trying to write to the status bar. */
-	if (!started_curses || isendwin()) {
+	if (isendwin()) {
 		fprintf(stderr, "Out of curses -- please report a bug\n");
 		lastmessage = HUSH;
 		napms(1400);