meta-google: Set VOLATILE_LOG_DIR to yes

The previous default behavior of /var/log directory being volatile is
removed in https://gerrit.openbmc.org/c/openbmc/openbmc/+/69959.

Set this to old behavior for Google machines.

Change-Id: I19b321ae5112434db68252d9bc40d646292fd970
Signed-off-by: Vivekanand Veeracholan <vveerach@google.com>
diff --git a/meta-google/conf/distro/gbmc.conf b/meta-google/conf/distro/gbmc.conf
index 1311aa7..89efcdc 100644
--- a/meta-google/conf/distro/gbmc.conf
+++ b/meta-google/conf/distro/gbmc.conf
@@ -46,3 +46,6 @@
 
 # Do not configure TPM layer
 SKIP_META_TPM_SANITY_CHECK = "1"
+
+# Set /var/log directory to be volatile
+VOLATILE_LOG_DIR = "yes"