CORD-1486 Set kernel boot options for nodes

Top-level config option like shown below should set the kernel boot options for the nodes.

kernel_opts: '''isolcpus=1-2 nohz_full=1-2 rcu_nocbs=1-2 hugepagesz=2M hugepages=1024'''

Change-Id: I36198254f220f04c192b0417b5926f3427db0033
diff --git a/build.gradle b/build.gradle
index 9d4b45c..1254337 100644
--- a/build.gradle
+++ b/build.gradle
@@ -311,6 +311,7 @@
             .p(config.common.virtualbox_support, "virtualbox_support")
             .p(config.common.power_helper_user, "power_helper_user")
             .p(config.common.power_helper_host, "power_helper_host")
+            .p(config.common.kernel_opts, "kernel_opts")
     }
 
     if (config.passwords) {
@@ -372,6 +373,7 @@
             .p(config.common.virtualbox_support, "virtualbox_support")
             .p(config.common.power_helper_user, "power_helper_user")
             .p(config.common.power_helper_host, "power_helper_host")
+            .p(config.common.kernel_opts, "kernel_opts")
     }
 
     if (config.passwords) {