staging: rtl8712: Improve naming of include hearder guards

staging: rtl8712: Improve naming of include hearder guards

Choose a better name for the include hearder guard used in rtl871x_io.h.
'_IO_H_' is to generic and does not match the comment after the #endif.
Use '_RTL871X_IO_H_' instead.

Also make the comments in the #endif /* XXX */ match the name used in
#ifndef.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20190818150609.3376-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>