package/libvirt: fix build with lvm2

libvirt needs a lvm2 standard install since its addition in commit
ccfc90e1010e42e6529afae3a5ea8bf7226dabc1 to avoid the following build
failure:

../output-1/build/libvirt-7.4.0/meson.build:1831:6: ERROR: Program 'pvcreate' not found

Fixes:
 - http://autobuild.buildroot.org/results/dc9af7a677af7e53c1240ebbee5b0edc84c8cf52

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit d0bd34ab2099494132a37c3f4a7e1e75cdc996da)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libvirt/libvirt.mk

@@ -166,7 +166,7 @@ else
 LIBVIRT_CONF_OPTS += -Dselinux=disabled -Dsecdriver_selinux=disabled
 endif
 
-ifeq ($(BR2_PACKAGE_LVM2),y)
+ifeq ($(BR2_PACKAGE_LVM2_STANDARD_INSTALL),y)
 LIBVIRT_CONF_OPTS += -Dstorage_lvm=enabled
 LIBVIRT_DEPENDENCIES += lvm2
 else