Staging: silicom: remove bp_media_type enum typedef

Remove the typedef for enum bp_media_type from bpctl_mod.c and
change its one use accordingly, resolving a checkpatch.pl warning.

Signed-off-by: Chad Williamson <chad@dahc.us>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>