Regenerate the system call stubs (to get x86_64).

This touches the x86 stubs too because arm, x86, and x86_64 now
all share the same header (at a source level), which causes a
reordering of the #include lines.

Change-Id: If9a1e2b2718bd41d8399fea748bce672c513ef84

libc/arch-x86_64/syscalls/capset.S

@@ -0,0 +1,17 @@
+/* autogenerated by gensyscalls.py */
+#include <asm/unistd.h>
+#include <linux/err.h>
+#include <machine/asm.h>
+
+ENTRY(capset)
+    movl    $__NR_capset, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno
+    orq     $-1, %rax
+1:
+    ret
+END(capset)