feat: update cpu governor to schedutil

This PR updates the default governor to "schedutil" away from
"userspace" on amd64 systems. Schedutil seems to be the default on
Ubuntu systems and the eventual default on all distros (already the
default on all ARM distros, including ours). I noticed no real
difference in sysbench testing between schedutil and ondemand, so I
believe this is a sane default choice for us. There was a very big diff
between the old value of userland, however, since there was no userland
process actually managing the frequencies.

Signed-off-by: Spencer Smith <spencer.smith@talos-systems.com>

kernel/kernel/config-amd64

@@ -555,8 +555,8 @@ CONFIG_CPU_FREQ_GOV_COMMON=y
 # CONFIG_CPU_FREQ_STAT is not set
 # CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
 # CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
-CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
-# CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set
+# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
+CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL=y
 CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
 # CONFIG_CPU_FREQ_GOV_POWERSAVE is not set
 CONFIG_CPU_FREQ_GOV_USERSPACE=y