target/i386/cpu: Remove unnecessary SGX feature words checks

target/i386/cpu: Remove unnecessary SGX feature words checks

CPUID.0x7.0.ebx and CPUID.0x7.0.ecx leaves have been expressed as the
feature word lists, and the Host capability support has been checked
in x86_cpu_filter_features().

Therefore, such checks on SGX feature "words" are redundant, and
the follow-up adjustments to those feature "words" will not actually
take effect.

Remove unnecessary SGX feature words related checks.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20240730045544.2516284-2-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>