x86: make machine/sysarch.h usable from assembler

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week

sys/x86/include/sysarch.h

@@ -71,6 +71,8 @@
 #define	AMD64_PKRU_EXCL		0x0001
 #define	AMD64_PKRU_PERSIST	0x0002
 
+#ifndef LOCORE
+
 struct i386_ioperm_args {
 	unsigned int start;
 	unsigned int length;
@@ -93,7 +95,7 @@ struct i386_get_xfpustate {
 	void *addr;
 	int len;
 };
-#else
+#else	/* __i386__ */
 struct i386_ldt_args {
 	unsigned int start;
 	struct user_segment_descriptor *descs __packed;
@@ -116,7 +118,7 @@ struct amd64_get_xfpustate {
 	void *addr;
 	int len;
 };
-#endif
+#endif	/* __i386__ */
 
 struct amd64_set_pkru {
 	void *addr;
@@ -153,7 +155,7 @@ int x86_pkru_protect_range(void *addr, unsigned long len, unsigned int keyidx,
 int x86_pkru_unprotect_range(void *addr, unsigned long len);
 int sysarch(int, void *);
 __END_DECLS
-#else
+#else	/* _KERNEL */
 struct thread;
 union descriptor;
 
@@ -167,6 +169,8 @@ int amd64_set_ldt(struct thread *, struct i386_ldt_args *,
 int amd64_get_ioperm(struct thread *, struct i386_ioperm_args *);
 int amd64_set_ioperm(struct thread *, struct i386_ioperm_args *);
 int amd64_pkru_update(struct thread *, uintptr_t, size_t, u_int, int, bool);
-#endif
+#endif	/* _KERNEL */
+
+#endif	/* LOCORE */
 
 #endif /* !_MACHINE_SYSARCH_H_ */