ncurses: add tmux terminfo

They're preferred terminal descriptions for tmux, with additional support to
some special characters and italic fonts. More info can be found at:
https://github.com/tmux/tmux/wiki/FAQ

Fixes: FS#3404

Signed-off-by: Jitao Lu <dianlujitao@gmail.com>
(cherry picked from commit 917126ff4c)

package/libs/ncurses/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=ncurses
 PKG_VERSION:=6.2
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=@GNU/$(PKG_NAME)
@@ -128,6 +128,8 @@ ifneq ($(HOST_OS),FreeBSD)
 		r/rxvt-unicode \
 		s/screen \
 		s/screen-256color \
+		t/tmux \
+		t/tmux-256color \
 		v/vt100 \
 		v/vt102 \
 		x/xterm \