print/pdf-tools: Add lexical-binding cookie to pdf-tools-init.el

As of 9f25d46568b in upstream's master branch, Emacs emits a run-time
warning when lexical binding is unset.  This serves as a reminder that
lexical binding is preferred.

Sponsored by:	The FreeBSD Foundation

print/pdf-tools/Makefile

@@ -1,7 +1,7 @@
 PORTNAME=	pdf-tools
 DISTVERSIONPREFIX=	v
 DISTVERSION=	1.1.0
-PORTREVISION=	12
+PORTREVISION=	13
 CATEGORIES=	print elisp
 PKGNAMESUFFIX=	${EMACS_PKGNAMESUFFIX}
 

print/pdf-tools/files/pdf-tools-init.el

@@ -1,3 +1,5 @@
+;;; pdf-tools-init.el --- PDF Tools Initialization -*- lexical-binding: t -*-
+
 (load "pdf-tools-loaddefs.el")
 (autoload 'pdf-view-mode "pdf-tools")
 (add-to-list 'auto-mode-alist '("\\.[pP][dD][fF]\\'" . pdf-view-mode))