arch/x86: Replace some __SMM__ guards

We generally do not guard source in attempts to reduce
the final object sizes, but rely on garbage collection.

Most of the __unused attributes inserted here will be
removed when remaining __SIMPLE_DEVICE__ guards can
be removed.

Change-Id: I2440931fab4f41d7e8249c082e6c9b5a9cd0ef13
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36641
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/southbridge/intel/lynxpoint/pch.c b/src/southbridge/intel/lynxpoint/pch.c
index dc7b958..cb50c12 100644
--- a/src/southbridge/intel/lynxpoint/pch.c
+++ b/src/southbridge/intel/lynxpoint/pch.c
@@ -90,7 +90,7 @@
 	return gpiobase;
 }
 
-#ifndef __SMM__
+#ifndef __SIMPLE_DEVICE__
 
 /* Put device in D3Hot Power State */
 static void pch_enable_d3hot(struct device *dev)
@@ -330,4 +330,4 @@
 	.enable_dev = pch_enable,
 };
 
-#endif /* __SMM__ */
+#endif /* __SIMPLE_DEVICE__ */