This patch removes re-definition of the following FVP build
options from plat\arm\board\fvp\fvp_def.h:
 'FVP_CLUSTER_COUNT'
 'FVP_MAX_CPUS_PER_CLUSTER'
 'FVP_MAX_PE_PER_CPU'
which are set in platform.mk.

This fixes a potential problem when a build option set in
platform.mk file can be re-defined in fvp_def.h header file
used by other build component with a different makefile which
does not set this option.
Ref. GENFW-3505.

Change-Id: I4288629920516acf2c239c7b733f92a0c5a812ff
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>