sysdev.h: dont include <linux/module.h> for no reason

The <linux/module.h> pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used <linux/something.h>
files, as it results in a measureable increase on compile times.

There doesn't appear to be any module specifics in this file.
The obvious people who were relying on the presence of
the vast amount of stuff module.h sucked in have been fixed.

If other files are implicitly relying on it, then lets see who
they are and fix them too.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>