vpn-policy-routing: Call killall with the -s

Some versions of killall do support the `killall -SIGNAL` syntax and
have only `-s SIGNAL` which should be supported everywhere.

I see the problem with *killall (PSmisc) 23.3* on latest TurrisOS 5.2

Signed-off-by: Jan Baier <jan.baier@amagical.net>

net/vpn-policy-routing/Makefile

@@ -5,7 +5,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=vpn-policy-routing
 PKG_VERSION:=0.3.5
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 PKG_LICENSE:=GPL-3.0-or-later
 PKG_MAINTAINER:=Stan Grishin <stangri@melmac.net>
 

net/vpn-policy-routing/files/vpn-policy-routing.init

@@ -154,7 +154,7 @@ is_domain() { str_contains "$1" '[a-zA-Z]'; }
 is_phys_dev() { [ "${1:0:1}" = "@" ] && ip l show | grep -E -q "^\\d+\\W+${1:1}"; }
 is_turris() { /bin/ubus -S call system board | /bin/grep 'Turris' | /bin/grep -q '15.05'; }
 is_chaos_calmer() { ubus -S call system board | grep -q 'Chaos Calmer'; }
-dnsmasq_kill() { killall -q -HUP dnsmasq; }
+dnsmasq_kill() { killall -q -s HUP dnsmasq; }
 dnsmasq_restart() { output 3 'Restarting DNSMASQ '; if /etc/init.d/dnsmasq restart >/dev/null 2>&1; then output_okn; else output_failn; fi; }
 is_default_dev() { [ "$1" = "$(ip -4 r | grep -m1 'dev' | grep -Eso 'dev [^ ]*' | awk '{print $2}')" ]; }
 is_supported_iface_dev() {