devel/gn: Drop -T from flags passed to ar

Remove -T flag from arguments passed to ar, because of planned -T flag
removal from ar in base and misusing. For now, switch to OpenBSD's build
template. The only difference with previously used Linux's build
template is this -T switch. NetBSD still use Linux's build template.

PR:		260596
Reviewed by:	emaste

devel/gn/Makefile

@@ -3,6 +3,7 @@
 PORTNAME=	gn
 DISTVERSIONPREFIX=	v
 DISTVERSION=	1962
+PORTREVISION=	1
 CATEGORIES=	devel
 
 MAINTAINER=	o.hushchenkov@gmail.com

devel/gn/files/patch-build_gen.py

@@ -1,6 +1,6 @@
 - .git/ is missing in archive, so use version from environment
 
---- build/gen.py.orig	2021-12-18 16:25:54 UTC
+--- build/gen.py.orig	2021-12-21 20:25:21 UTC
 +++ build/gen.py
 @@ -213,25 +213,16 @@ def main(argv):
  
@@ -30,3 +30,12 @@
  
    # Only write/touch this file if the commit position has changed.
    old_contents = ''
+@@ -274,7 +265,7 @@ def WriteGenericNinja(path, static_libraries, executab
+       'msys': 'build_linux.ninja.template',
+       'darwin': 'build_mac.ninja.template',
+       'linux': 'build_linux.ninja.template',
+-      'freebsd': 'build_linux.ninja.template',
++      'freebsd': 'build_openbsd.ninja.template',
+       'aix': 'build_aix.ninja.template',
+       'openbsd': 'build_openbsd.ninja.template',
+       'haiku': 'build_haiku.ninja.template',