Revert "ext4: verify dir block before splitting it"

This reverts commit 17034d45 which is
commit 46c116b9 upstream,  as it breaks
the build in Android kernel builds due to out-of-tree changes that were
never merged upstream.

Bug: 236690716
Fixes: bc1a5b8c ("Merge 4.14.283 into android-4.14-stable")
Cc: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I08929715fb488a7d1977300e84d0940a9bf4dc98