config: disable memory cgroups to save memory

2MB of memory are allocated by the kernel for memory cgroups
while we never use them on our devices, so disable support in defconfig

Change-Id: I9591e0c8836868a2fb2472cb1e843efe8432a359
Tracked-On: https://jira01.devtools.intel.com/browse/AW-4485


Signed-off-by: Simon Dubray <simonx.dubray@intel.com>
Reviewed-on: https://android.intel.com/571034


Reviewed-by: jenkins_ndg <jenkins_ndg@intel.com>
Reviewed-by: Ledentec, AlexandreX <alexandrex.ledentec@intel.com>
Reviewed-by: Louis, FabienX <fabienx.louis@intel.com>
Reviewed-by: Deverge, Jean-francoisX <jean-francoisx.deverge@intel.com>
Reviewed-by: Ben Alaya, AymenX <aymenx.ben.alaya@intel.com>
Reviewed-by: Whitfield, MichaelX <michaelx.whitfield@intel.com>
Reviewed-by: Tasayco Loarte, VictorX <victorx.tasayco.loarte@intel.com>
Reviewed-by: Korpershoek, MattijsX <mattijsx.korpershoek@intel.com>