Revert "debugfs: add the hexdump_block command"

This reverts commit 58b0356a251a6bc7703a482bea5d1fe6766a65c5.

We already have the block_dump (bd) command, but I had completely
forgotten about it.  Oops!

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
4 files changed