io_fip: return -ENFILE when a file is already open

The cause of failure is not memory shortage.

The comment for ENFILE in include/lib/libc/errno.h

  /* Too many open files in system */

... is a better match to the warning message here.

Change-Id: I45a1740995d464edd8b3e32b93f1f92ba17e5874
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
1 file changed