This reverts commit 0bdebfef3fb2b6291000765eaa9c6c8030293fce. XCP_CTL register is programmed by firmware and register access is protected. Signed-off-by: Mangesh Gadre <Mangesh.Gadre@amd.com> Reviewed-by: Lijo Lazar <lijo.lazar@amd.com> Reviewed-by: Asad Kamal <asad.kamal@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>