[vbox-dev] Cleanig up warnigs - and for the maniacs out there.. :)

[Valdis Kl=?utf-8?Q?=c4=93?=tnieks]

The bad news:  building with 'make W=1' throws 1,242 lines of warnings.

The not-so-bad news: 

Of those, 811 are kerneldoc warnings for function declarations, of the form:
 warning: Function parameter or member 'pGlobals' not described in 'vboxPciNewInstance'

Another 47 are other kerneldoc warnings where it thinks there's a kerneldoc
comment attached to a struct rather than a function and other similar.

It's possible that a large percentage of those are common blocks that aren't
intended to be kerneldoc, but they start with '/**' instead of '/*' so they end
up looking like kerneldoc, I didn't check further.

There's 224 occurences of "warning: Using plain integer as NULL pointer"
which are all places where there's a '0' instead of NULL.

64 are related to mixing gfp_t and other types in r0drv/linux/memobj-r0drv-linux.c

leaving only 68 for everything else. Actually not that bad at all for an
out-of-tree module of this size.

No, I'm not going to submit patches, I've got a big enough patch queue trying
to make the Linux kernel safer for building with W=1. :)