package/libgit2: bump to version 1.8.0

The license file was updated for two reasons:
* This version now bundles ntlmclient.  NTLM support is disabled by
  the buildroot package.
* The bundled zlib version (that buildroot does not use) was updated and
  its copyright years changed.

This version also adds support for using the SSH binary (at an hardcoded
/usr/bin/ssh path) instead of using libssh2.

Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/libgit2/libgit2.hash

@@ -1,3 +1,3 @@
 # Locally calculated
-sha256  de384e29d7efc9330c6cdb126ebf88342b5025d920dcb7c645defad85195ea7f  libgit2-1.7.2.tar.gz
-sha256  6f3c2cd59b057e366c1acc073b038135c52d77892bb33bd4d931c5369d3f062b  COPYING
+sha256  9e1d6a880d59026b675456fbb1593c724c68d73c34c0d214d6eb848e9bbd8ae4  libgit2-1.8.0.tar.gz
+sha256  08041a7e9c4d0e5e84f9711c824a0bd0366ee782ec29c6d7275fdab73e2ca115  COPYING

package/libgit2/libgit2.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-LIBGIT2_VERSION = 1.7.2
+LIBGIT2_VERSION = 1.8.0
 LIBGIT2_SITE = $(call github,libgit2,libgit2,v$(LIBGIT2_VERSION))
 LIBGIT2_LICENSE = \
 	GPL-2.0 with linking exception, \
@@ -42,7 +42,9 @@ endif
 
 ifeq ($(BR2_PACKAGE_LIBSSH2),y)
 LIBGIT2_DEPENDENCIES += libssh2
-LIBGIT2_CONF_OPTS += -DUSE_SSH=ON
+LIBGIT2_CONF_OPTS += -DUSE_SSH=libssh2
+else ifeq ($(BR2_PACKAGE_OPENSSH_CLIENT),y)
+LIBGIT2_CONF_OPTS += -DUSE_SSH=exec
 else
 LIBGIT2_CONF_OPTS += -DUSE_SSH=OFF
 endif