netem: remove unnecessary 64 bit modulus

Fix compilation on 32 bit platforms (where doing modulus operation
with 64 bit requires extra glibc functions) by truncation.
The jitter for table distribution is limited to a 32 bit value
because random numbers are scaled as 32 bit value.

Also fix some whitespace.

Fixes: 99803171 ("netem: add uapi to express delay and jitter in nanoseconds")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>