Use a proper definition of tputs.

--- irssi-1.4.4/src/fe-text/term-terminfo.c	2023-03-28 13:13:26.000000000 +0100
+++ irssi-1.4.4/src/fe-text/term-terminfo.c	2025-07-04 04:42:14.857313179 +0100
@@ -29,6 +29,7 @@
 #include <signal.h>
 #include <termios.h>
 #include <stdio.h>
+#include <termcap.h>
 
 /* returns number of characters in the beginning of the buffer being a
    a single character, or -1 if more input is needed. The character will be
@@ -314,9 +315,6 @@
         return fputc(c, current_term->out);
 }
 
-/* copied from terminfo-core.c */
-int tputs();
-
 static int termctl_set_color_24bit(int bg, unsigned int lc)
 {
 	static char buf[20];