Remove swapiness settings from sysctl.conf

On some of our images swapiness (as set for reasons described in
I09974be88cc590cf9ffbd16db58c19131c9532aa) is in /etc/sysctl.conf, so
a "sysctl -p" call done later can overwrite the value we want set.

Change-Id: Ic46c4b9b80335c4c4ad58f9593927743cc1f4fab

functions.sh

@@ -290,7 +290,9 @@ function fix_disk_layout {
     # kicking in on some processes despite swap being available;
     # particularly things like mysql which have very high ratio of
     # anonymous-memory to file-backed mappings.
-    #
+
+    # make sure reload of sysctl doesn't reset this
+    sudo sed -i '/vm.swappiness/d' /etc/sysctl.conf
     # This sets swappiness low; we really don't want to be relying on
     # cloud I/O based swap during our runs
     sudo sysctl -w vm.swappiness=10