resize2fs: fix on-line resizing

resize2fs: fix on-line resizing

On-line resizing has been broken in the 1.42 series for two reasons:
(a) the call to the new EXT4_IOC_RESIZE_FS ioctl checked for ENOTTY to
indicate that the ioctl does not exist, when in fact EINVAL is what is
returned if the ioctl doesn't exist.  (b) resize2fs was passing in a
pointer to a 64-bit value, when the ioctl expected a 32-bit value.
This was OK on little-endian systems, but it wouldn't work at all on
big-endian systems.

Fix both problems.

Addresses-Debian-Bug: #451388

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