openpower: ekb: srcrev bump a9996cb6..efd3569c4d

Commits included:
 - Change ATTR_FREQ_MC_MHZ to 146
 - Updates with latest pub-ekb version

Signed-off-by: Chirag Sharma <chirshar@in.ibm.com>
diff --git a/openpower/package/ekb/Config.in b/openpower/package/ekb/Config.in
index a9b93a8..9233677 100644
--- a/openpower/package/ekb/Config.in
+++ b/openpower/package/ekb/Config.in
@@ -30,7 +30,7 @@
 
 config BR2_EKB_VERSION
     string
-    default "a9996cb6861198688010522baed369b0af0e6aca" if BR2_EKB_LATEST_VERSION
+    default "efd3569c4d8c4c545620539edc0515ec68b78f43" if BR2_EKB_LATEST_VERSION
     default BR2_EKB_CUSTOM_VERSION_VALUE if BR2_EKB_CUSTOM_VERSION
 endif