security/easy-rsa: fix cert issuance with BSD grep

easyrsa running on systems with bsdgrep for grep
fails issuing certs because it attempts \d as shorthand for
[[:digit:]] or [0-9] and triggers a grep failure with diagnostic

    grep: trailing backslash (\)

Filed upstream: OpenVPN/easy-rsa#556

PR:		263812
Submitted by:	grembo@

security/easy-rsa/Makefile

@@ -1,5 +1,6 @@
 PORTNAME=	easy-rsa
 DISTVERSION=	3.0.8
+PORTREVISION=	1
 CATEGORIES=	security net-mgmt
 MASTER_SITES=	https://github.com/OpenVPN/easy-rsa/releases/download/v${DISTVERSION}/
 DISTNAME=	EasyRSA-${DISTVERSION}

security/easy-rsa/files/patch-easyrsa

@@ -0,0 +1,11 @@
+--- easyrsa.orig	2020-09-09 20:59:45 UTC
++++ easyrsa
+@@ -1546,7 +1546,7 @@ default_server_san() {
+ 		easyrsa_openssl req -in "$path" -noout -subject -nameopt sep_multiline |
+ 		awk -F'=' '/^  *CN=/{print $2}'
+ 		)
+-	echo "$cn" | grep -E -q '^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$'
++	echo "$cn" | grep -E -q '^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$'
+ 	#shellcheck disable=SC2181
+ 	if [ $? -eq 0 ]; then
+ 		print "subjectAltName = IP:$cn"