[SPARC]: Fix robust futex syscalls and wire up migrate_pages.

When I added the entries for the robust futex syscall entries, I
forgot to bump NR_SYSCALLS.  The current situation is error-prone
because NR_SYSCALLS lives in entry.S where the system call limit
checks are enforced.  Move the definition to asm/unistd.h in order to
make this mistake much more difficult to make.

And wire up sys_migrate_pages since the powerpc folks implemented the
compat wrapper for us.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index a4edff4..831f540 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -32,13 +32,12 @@
 #include <asm/mxcc.h>
 #include <asm/thread_info.h>
 #include <asm/param.h>
+#include <asm/unistd.h>
 
 #include <asm/asmmacro.h>
 
 #define curptr      g6
 
-#define NR_SYSCALLS 300      /* Each OS is different... */
-
 /* These are just handy. */
 #define _SV	save	%sp, -STACKFRAME_SZ, %sp
 #define _RS     restore