[IA64] Wire up kcmp syscall

systemd > 218 fails to compile on ia64 with:

     error: ‘__NR_kcmp’ undeclared [1].

I've been told that this is because the kcmp syscall hasn't been wired up
for the ia64 arch [2].

The proposed patch thus wire up the kcmp syscall for the ia64 arch.

[1] https://bugs.gentoo.org/show_bug.cgi?id=560492
[2] https://bugs.gentoo.org/show_bug.cgi?id=560492#c17

Signed-off-by: Émeric MASCHINO <emeric.maschino@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/include/asm/unistd.h

@@ -11,7 +11,7 @@
 
 
 
-#define NR_syscalls			321 /* length of syscall table */
+#define NR_syscalls			322 /* length of syscall table */
 
 /*
  * The following defines stop scripts/checksyscalls.sh from complaining about

arch/ia64/include/uapi/asm/unistd.h

@@ -334,5 +334,6 @@
 #define __NR_execveat			1342
 #define __NR_userfaultfd		1343
 #define __NR_membarrier			1344
+#define __NR_kcmp			1345
 
 #endif /* _UAPI_ASM_IA64_UNISTD_H */

arch/ia64/kernel/entry.S

@@ -1770,5 +1770,6 @@ sys_call_table:
 	data8 sys_execveat
 	data8 sys_userfaultfd
 	data8 sys_membarrier
+	data8 sys_kcmp				// 1345
 
 	.org sys_call_table + 8*NR_syscalls	// guard against failures to increase NR_syscalls