support _POSIX_REALTIME_SIGNALS

Bug: 18489947
Change-Id: I2e834d68bc10ca5fc7ebde047b517a3074179475
diff --git a/libc/arch-x86_64/syscalls/__rt_sigqueueinfo.S b/libc/arch-x86_64/syscalls/__rt_sigqueueinfo.S
new file mode 100644
index 0000000..52b6863
--- /dev/null
+++ b/libc/arch-x86_64/syscalls/__rt_sigqueueinfo.S
@@ -0,0 +1,16 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(__rt_sigqueueinfo)
+    movl    $__NR_rt_sigqueueinfo, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno_internal
+1:
+    ret
+END(__rt_sigqueueinfo)
+.hidden __rt_sigqueueinfo