fsck: warn if fsck.<type> not found and device is specified

fsck: warn if fsck.<type> not found and device is specified

The fsck(8) command prints an error for certain 'required'
filesystems, such as extN, if the corresponding fsck.<type> helper is
not found. However, for other filesystems, it silently ignores the
device. While this behavior is acceptable for the -A option, if a user
explicitly specifies the device on the command line, it is probably a
good idea to be more verbose and issue a warning that the device will
be ignored. The warning is enabled only for interactive mode (only one
device specified or -s).

Note that some filesystems do not have an fsck utility, so caution is
needed when issuing such warnings to prevent the generation of a large
number of unwanted entries in system logs, etc."

Reported-by: наб <nabijaczleweli@nabijaczleweli.xyz>
Signed-off-by: Karel Zak <kzak@redhat.com>