x86/xen: Fix xen head ELF annotations

Mark the ends of the startup_xen and hypercall_page code sections.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3a80a394d30af43d9cefa1a29628c45ed8420c97.1505764066.git.jpoimboe@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/xen/xen-head.S

@@ -33,7 +33,7 @@ ENTRY(startup_xen)
 	mov $init_thread_union+THREAD_SIZE, %_ASM_SP
 
 	jmp xen_start_kernel
-
+END(startup_xen)
 	__FINIT
 #endif
 
@@ -47,7 +47,7 @@ ENTRY(hypercall_page)
 	.type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
 #include <asm/xen-hypercalls.h>
 #undef HYPERCALL
-
+END(hypercall_page)
 .popsection
 
 	ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,       .asciz "linux")