examples: x86: delete 82559_eeprom

Commit fea25720 renamed arch/i386 to arch/x86.
But it missed to modify examples/standalone/Makefile.

Since then, examples/standalone/82559_eeprom has
never compiled and nobody has noticed that.

After some discussion on ML, we agreed to delete this example.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>