Capture the value of "errno" in semihosting isatty() call,
as is done in other syscalls.
Change-Id: I41b72175635f06c000536f583e3efa30fb57379e
Signed-off-by: Jan Matyas <matyas@codasip.com>
Reviewed-on: http://openocd.zylin.com/6292
Tested-by: jenkins
Reviewed-by: Tim Newsome <tim@sifive.com>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>