openvpn: explicitly disable engine parameter for openssl variant

Engine support is deprecated in OpenSSL 3.0 and for OpenSSL 3.0 the default
is to disable engine support as engine support is deprecated. For ath79 architecture
build with autodetection engine support fails, so explicitly set off for now.

Signed-off-by: Ivan Pavlov <AuthorReflex@gmail.com>
(cherry picked from commit 62e909e845)

net/openvpn/Makefile

@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 PKG_NAME:=openvpn
 
 PKG_VERSION:=2.5.7
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE_URL:=\
 	https://build.openvpn.net/downloads/releases/ \
@@ -87,7 +87,7 @@ define Build/Configure
 		$(if $(CONFIG_OPENVPN_$(BUILD_VARIANT)_ENABLE_DEF_AUTH),--enable,--disable)-def-auth \
 		$(if $(CONFIG_OPENVPN_$(BUILD_VARIANT)_ENABLE_PF),--enable,--disable)-pf \
 		$(if $(CONFIG_OPENVPN_$(BUILD_VARIANT)_ENABLE_PORT_SHARE),--enable,--disable)-port-share \
-		$(if $(CONFIG_OPENVPN_OPENSSL),--with-crypto-library=openssl) \
+		$(if $(CONFIG_OPENVPN_OPENSSL),--with-crypto-library=openssl --with-openssl-engine=no) \
 		$(if $(CONFIG_OPENVPN_MBEDTLS),--with-crypto-library=mbedtls) \
 		$(if $(CONFIG_OPENVPN_WOLFSSL),--with-crypto-library=wolfssl) \
 	)