radv: fix radv secure compile feature breaks compilation on armhf EABI and aarch64

__NR_select is not defined the same way across architectures, sometimes is not even defined, like in armhf EABI and aarch64.

Closes: #2042 (closed)

Signed-off-by: Luis Mendes luis.p.mendes@gmail.com

Acked-by: Timothy Arceri tarceri@itsqueeze.com

Acked-by: Samuel Pitoiset samuel.pitoiset@gmail.com