[stdio] Remove unused <sys/select.h> inclusion Change-Id: I1da7eea7058900d8ed7c870afea107e23e927367
[utest] Include copyright notice and header guard in stdio test Change-Id: I79271f70472fb59deefaefa27809fb4d1b30f594
[utest] Added utest/stdio tests Change-Id: I6349366a9a1add07c0738aa480948cb2a2a75286