bug#15680: dd: suggest iflag=fullblock ... but only if count > 1

[Bernhard Voelker]

dd(1) issues a nice warning about short reads ...

  src/dd if=/dev/random of=sample bs=1000 count=2
  src/dd: warning: partial read (128 bytes); suggest iflag=fullblock
  0+2 records in
  0+2 records out
  256 bytes (256 B) copied, 0.000423371 s, 605 kB/s

... but only if count was > 1:

  src/dd if=/dev/random of=sample bs=1000 count=1
  0+1 records in
  0+1 records out
  128 bytes (128 B) copied, 0.000270231 s, 474 kB/s

Is this by intension or an off-by-one?
I'd like to provide a patch in the latter case.

Have a nice day,
Berny