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.comReviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/dell/dcdbas.c

@@ -394,8 +394,7 @@ static int host_control_smi(void)
 
 		/* wait a few to see if it executed */
 		num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
-		while ((cmd_status = inb(PCAT_APM_STATUS_PORT))
-		       == ESM_STATUS_CMD_UNSUCCESSFUL) {
+		while ((s8)inb(PCAT_APM_STATUS_PORT) == ESM_STATUS_CMD_UNSUCCESSFUL) {
 			num_ticks--;
 			if (num_ticks == EXPIRED_TIMER)
 				return -ETIME;