net: stmmac: enable platform specific safety features

On Intel platforms, not all safety features are enabled on the hardware.
The current implementation enable all safety features by default. This
will cause mass error and warning printouts after the module is loaded.

Introduce platform specific safety features flag to enable or disable
each safety features.

Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>