linux/hdsmart.h: fix goofups (take 2)

Fix goofups of commit 76166952bbc81dda1c8a8c14e75a2aa06f6c052c
("<linux/hdsmart.h> is not used by kernel code").

Also update include/linux/Kbuild to reflect the fact that hdsmart.h
uses __KERNEL__ ifdefs now.

Reported-by: "Robert P. J. Day" <rpjday@crashcourse.ca>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/hdsmart.h b/include/linux/hdsmart.h
index e691921..4f4faf9 100644
--- a/include/linux/hdsmart.h
+++ b/include/linux/hdsmart.h
@@ -17,7 +17,7 @@
 #ifndef _LINUX_HDSMART_H
 #define _LINUX_HDSMART_H
 
-#ifndef __KERNEL
+#ifndef __KERNEL__
 #define OFFLINE_FULL_SCAN		0
 #define SHORT_SELF_TEST			1
 #define EXTEND_SELF_TEST		2
@@ -121,6 +121,6 @@
 	unsigned char			resevered[2];
 	unsigned char			chksum;
 } __attribute__ ((packed)) ata_smart_selftestlog_t;
-#endif /* __KERNEL__ *
+#endif /* __KERNEL__ */
 
 #endif	/* _LINUX_HDSMART_H */