x11-toolkits/pango: track libthai dependency

Error: /usr/local/lib/libpango-1.0.so.0.5000.9 is linked to /usr/local/lib/libthai.so.0 from devel/libthai but it is not declared as a dependency
Warning: you need LIB_DEPENDS+=libthai.so:devel/libthai

PR:		270361

x11-toolkits/pango/Makefile

@@ -1,5 +1,6 @@
 PORTNAME=	pango
 PORTVERSION=	1.50.9
+PORTREVISION=	1
 CATEGORIES=	x11-toolkits
 MASTER_SITES=	GNOME
 DIST_SUBDIR=	gnome2
@@ -34,14 +35,18 @@ FONTSCALE=	${LOCALBASE}/share/fonts/TTF/luximb.ttf
 FONTENCOD=	${LOCALBASE}/share/fonts/encodings/encodings.dir
 
 OPTIONS_SUB=	yes
-OPTIONS_DEFINE=	X11 DOCS MANPAGES
-OPTIONS_DEFAULT=X11 MANPAGES
+OPTIONS_DEFINE=	X11 DOCS MANPAGES THAI
+OPTIONS_DEFAULT=X11 MANPAGES THAI
 
 DOCS_MESON_TRUE=	gtk_doc
 DOCS_BUILD_DEPENDS=	${PYTHON_PKGNAMEPREFIX}gi-docgen>=0:textproc/py-gi-docgen
 
 MANPAGES_BUILD_DEPENDS=	help2man:misc/help2man
 
+THAI_DESC=		Thai language support via libThai
+THAI_LIB_DEPENDS=	libthai.so:devel/libthai
+THAI_MESON_ENABLED=	libthai
+
 X11_MESON_ENABLED=	xft
 X11_USES=	xorg
 X11_USE=	XORG=x11,xft,xrender