[SCSI] nsp32: use mdelay instead of large udelay constants

ARM cannot handle udelay for more than 2 miliseconds, so we
should use mdelay instead for those.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: GOTO Masanori <gotom@debian.or.jp>
Cc: YOKOTA Hiroshi <yokota@netlab.is.tsukuba.ac.jp>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-scsi@vger.kernel.org