platform/x86: dcdbas: drop unneeded assignment in host_control_smi()

platform/x86: dcdbas: drop unneeded assignment in host_control_smi()

Making '==' operation with ESM_STATUS_CMD_UNSUCCESSFUL directly
after calling the function inb() is more efficient, so assignment
to 'cmd_status' is redundant.

Eliminate the following clang_analyzer warning:
drivers/platform/x86/dell/dcdbas.c:397:11: warning: Although the value
stored to 'cmd_status' is used in the enclosing expression, the value
is never actually read from 'cmd_status'

No functional change.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/1620809825-84105-1-git-send-email-yang.lee@linux.alibaba.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>