libssh2: version bump

- Bump version to 1.8.0
- Switch from openssl crypto backend to mbedtls (the package is a lot
  smaller size-wise compared to openssl and libgcrypt)
- mbedtls support was added in 1.8.0 release. Unfortunately the detection
  doesn't work out of the box, so a patch is needed that fixes an m4
  script. For that reason autoreconf must be run.
- Add --with-libz-prefix as without it zlib is not detected (currently
  there is the zlib dependency but libssh2 never actually links to it).
- Add --disable-silent-rules to get verbose build output.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

libs/libssh2/Makefile

@@ -1,5 +1,5 @@
 #
-# Copyright (C) 2015-2016 OpenWrt.org
+# Copyright (C) 2015-2018 OpenWrt.org
 #
 # This is free software, licensed under the GNU General Public License v2.
 # See /LICENSE for more information.
@@ -8,12 +8,14 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libssh2
-PKG_VERSION:=1.7.0
+PKG_VERSION:=1.8.0
 PKG_RELEASE:=1
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
-PKG_SOURCE_URL:=http://www.libssh2.org/download
-PKG_HASH:=e4561fd43a50539a8c2ceb37841691baf03ecb7daf043766da1b112e4280d584
+PKG_SOURCE_URL:=https://www.libssh2.org/download
+PKG_HASH:=39f34e2f6835f4b992cafe8625073a88e5a28ba78f83e8099610a7b3af4676d4
+
+PKG_FIXUP:=autoreconf
 
 PKG_INSTALL:=1
 
@@ -26,8 +28,8 @@ define Package/libssh2
   SECTION:=libs
   CATEGORY:=Libraries
   TITLE:=SSH2 library
-  URL:=http://www.libssh2.org/
-  DEPENDS:=+libopenssl +zlib
+  URL:=https://www.libssh2.org/
+  DEPENDS:=+libmbedtls +zlib
   MAINTAINER:=Jiri Slachta <jiri@slachta.eu>
 endef
 
@@ -39,7 +41,10 @@ TARGET_CFLAGS += $(FPIC)
 
 CONFIGURE_ARGS += \
 	--disable-examples-build \
-	--with-libssl-prefix=$(STAGING_DIR)/usr
+	--disable-silent-rules \
+	--with-mbedtls \
+	--with-libmbedtls-prefix=$(STAGING_DIR)/usr \
+	--with-libz-prefix=$(STAGING_DIR)/usr
 
 define Build/InstallDev
 	$(INSTALL_DIR) $(1)/usr/include