openssh-server: deprecate the ecdsa HostKey

The init.d script for sshd never generates an ecdsa HostKey as seen
here:

	for type in rsa ed25519
	do
		# check for keys
		key=/etc/ssh/ssh_host_${type}_key
		[ ! -f $key ] && {
			# generate missing keys
			[ -x /usr/bin/ssh-keygen ] && {
				/usr/bin/ssh-keygen -N '' -t $type -f $key 2>&- >&-
			}
		}
	done

so we'll never succeed at loading one.  Get rid of the resultant
error message in logging:

May  5 17:13:59 OpenWrt sshd[20070]: error: Unable to load host key: /etc/ssh/ssh_host_ecdsa_key

Signed-off-by: Philip Prindeville <philipp@redfish-solutions.com>

net/openssh/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=openssh
 PKG_VERSION:=8.2p1
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/ \
@@ -227,7 +227,7 @@ define Package/openssh-server/install
 	$(INSTALL_DIR) $(1)/etc/ssh
 	chmod 0700 $(1)/etc/ssh
 	$(INSTALL_DATA) $(PKG_INSTALL_DIR)/etc/ssh/sshd_config $(1)/etc/ssh/
-	sed -r -i 's,^#(HostKey /etc/ssh/ssh_host_(rsa|ecdsa|ed25519)_key)$$$$,\1,' $(1)/etc/ssh/sshd_config
+	sed -r -i 's,^#(HostKey /etc/ssh/ssh_host_(rsa|ed25519)_key)$$$$,\1,' $(1)/etc/ssh/sshd_config
 	$(INSTALL_DIR) $(1)/etc/init.d
 	$(INSTALL_BIN) ./files/sshd.init $(1)/etc/init.d/sshd
 	$(INSTALL_DIR) $(1)/usr/sbin