arch/x86: Create helper for APM_CNT SMI triggers

Attempts to write to APM_CNT IO port should always be guarded
with a test to verify SMI handler has been installed.

Immediate followup removes redundant HAVE_SMI_HANDLER tests.

Change-Id: If3fb0f1a8b32076f1d9f3fea9f817dd4b093ad98
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41971
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/intel/broadwell/lpc.c b/src/soc/intel/broadwell/lpc.c
index 5cfeb5f..d5f8451 100644
--- a/src/soc/intel/broadwell/lpc.c
+++ b/src/soc/intel/broadwell/lpc.c
@@ -410,9 +410,7 @@
 static void pch_set_acpi_mode(void)
 {
 	if (CONFIG(HAVE_SMI_HANDLER) && !acpi_is_wakeup_s3()) {
-		printk(BIOS_DEBUG, "Disabling ACPI via APMC:\n");
-		outb(APM_CNT_ACPI_DISABLE, APM_CNT);
-		printk(BIOS_DEBUG, "done.\n");
+		apm_control(APM_CNT_ACPI_DISABLE);
 	}
 }