libssh: upgrade to 0.8.4

Notable changes since 0.7.3:
  * Fixed CVE-2018-10933 authentication bypass
  * Removed support for deprecated SSHv1 protocol
  * Added support for OpenSSL 1.1
  * Added support for chacha20-poly1305 cipher
  * Added ECDSA support with gcrypt backend
  * Improved threading support (note: libssh_threads is now gone)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-support/libssh/libssh_0.8.4.bb

@@ -0,0 +1,33 @@
+SUMMARY = "Multiplatform C library implementing the SSHv2 and SSHv1 protocol"
+HOMEPAGE = "http://www.libssh.org"
+SECTION = "libs"
+LICENSE = "LGPLv2.1"
+LIC_FILES_CHKSUM = "file://COPYING;md5=388a4fb1dea8ceae0be78ba9b01fc139"
+
+DEPENDS = "zlib openssl libgcrypt"
+
+SRC_URI = "git://git.libssh.org/projects/libssh.git;branch=stable-0.8"
+SRCREV = "789df0b7d0c7abd6b85db9fc5247e146e3d4ddba"
+
+S = "${WORKDIR}/git"
+
+inherit cmake
+
+PACKAGECONFIG ??=""
+PACKAGECONFIG[gssapi] = "-DWITH_GSSAPI=1, -DWITH_GSSAPI=0, krb5, "
+
+EXTRA_OECMAKE = " \
+    -DWITH_GCRYPT=1 \
+    -DWITH_PCAP=1 \
+    -DWITH_SFTP=1 \
+    -DWITH_ZLIB=1 \
+    -DLIB_SUFFIX=${@d.getVar('baselib').replace('lib', '')} \
+    "
+
+do_configure_prepend () {
+    # Disable building of examples
+    sed -i -e '/add_subdirectory(examples)/s/^/#DONOTWANT/' ${S}/CMakeLists.txt \
+        || bbfatal "Failed to disable examples"
+}
+
+TOOLCHAIN = "gcc"