package/libvirt: disable sasl

sasl depends on libsasl2 (https://github.com/cyrusimap/cyrus-sasl) which
is not packaged yet in buildroot and will result in the following build
failure raised since commit fbf25acfbfd5a73b3560918bea081768abbe5723:

output/build/libvirt-7.7.0/meson.build:1212:2: ERROR: Dependency "libsasl2" not found, tried pkgconfig

Fixes:
 - No autobuilder failures (yet)

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/libvirt/libvirt.mk

@@ -63,6 +63,7 @@ LIBVIRT_CONF_OPTS = \
 	-Dpciaccess=enabled \
 	-Dpm_utils=disabled \
 	-Dsanlock=disabled \
+	-Dsasl=disabled \
 	-Dsecdriver_apparmor=disabled \
 	-Dstorage_iscsi=disabled \
 	-Dstorage_iscsi_direct=disabled \
@@ -212,13 +213,6 @@ else
 LIBVIRT_CONF_OPTS += -Dnss=disabled
 endif
 
-ifeq ($(BR2_PACKAGE_LIBGSASL),y)
-LIBVIRT_CONF_OPTS += -Dsasl=enabled
-LIBVIRT_DEPENDENCIES += libgsasl
-else
-LIBVIRT_CONF_OPTS += -Dsasl=disabled
-endif
-
 ifeq ($(BR2_PACKAGE_LIBSSH2),y)
 LIBVIRT_CONF_OPTS += -Dlibssh2=enabled
 LIBVIRT_DEPENDENCIES += libssh2