Staging: bcm: Use udelay instead of msleep for delays in nvm.c

This patch uses udelay instead of msleep for delays
because msleep can sleep up to 20ms for any value
less than 20.

Signed-off-by: Kevin McKinney <klmckinney1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>