fix(cpufeat): resolve build errors due to compiler optimization

Currently most of the architectural feature build flags are set
to 2(FEATURE_STATE_CHECK) for fvp platform only.

However other platforms still configure them by default to 0, which
would lead to build failures in cases when compiler configured
to build TF-A  with zero optimization (CFLAGS='-O0').

This patch addresses such build issues and thereby resolves the failures
seen under CI-l3 test_configurations.

Change-Id: I45b82b821951bba6b9df08177f7d286e624a4239
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>