ext4_xattr_check_entry() was redundant with validation of the full xattr
entries list in ext4_xattr_check_entries(), which all callers also did.
ext4_xattr_check_entry() also didn't actually do correct validation;
specifically, it never checked that the value doesn't overlap the xattr
names, nor did it account for padding when checking whether the xattr
value overflows the available space.  So remove it to eliminate any
potential confusion.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>