pc80/mc146818rtc.h: Has X86 specific inlines without guards

PC80 header components are winding up in ARM builds with static inline
X86 specific code.

Change-Id: Ib23e70a34c478dc099b84b59a5234539cc2482e3
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/6101
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <gaumless@gmail.com>

src/include/pc80/i8254.h

@@ -59,4 +59,5 @@
 #define PPCB_T2GATE     0x01    /* Bit 0 */
 
 void setup_i8254(void);
-#endif
+
+#endif /* PC80_I8254_H */

src/include/pc80/mc146818rtc.h

@@ -1,6 +1,8 @@
 #ifndef PC80_MC146818RTC_H
 #define PC80_MC146818RTC_H
 
+#if CONFIG_ARCH_X86
+
 #include <arch/io.h>
 #include <types.h>
 
@@ -224,4 +226,6 @@ void cmos_post_log(void);
 static inline void cmos_post_log(void) {}
 #endif /* CONFIG_CMOS_POST */
 
+#endif /* CONFIG_ARCH_X86 */
+
 #endif /*  PC80_MC146818RTC_H */