[PATCH] ide-floppy: fix IDEFLOPPY_TICKS_DELAY

* IDEFLOPPY_TICKS_DELAY assumed HZ == 100, fix it
* increase the delay to 50ms (to match comment in the code)

Thanks to Manfred Scherer <manfred.scherer.mhm@t-online.de>
for reporting the problem and testing the patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>