[PATCH] RH9 kernel compatibility

This patch against CVS also applies to comedi-0.7.69 and allows it to 
compile correctly against Red Hat 9's 2.4.20-8 kernel, and probably 
others using the "statm" kernel patch.  It also changes the conditions 
for defining the pte_offset_kernel() macro in the asm/pgtable.h 
compatibility header to avoid it being redefined.

I have tested that comedi-0.7.69 compiles okay, but haven't tested 
installation; I don't have RH9 installed and couldn't get the kernel to 
compile on my Gentoo system - probably due to a gcc incompatibility.

Although comedi-0.7.69 compiles okay, this patch alone is not sufficient 
to compile the CVS version for the RH9 kernel.  It failed to compile the 
das08_cs driver.  I'll look into it.

-- 
-=( Ian Abbott _at_ MEV Ltd.    E-mail: <abbotti_at_mev.co.uk>        )=-
-=( Tel: +44 (0)161 477 1898   FAX: +44 (0)161 718 3587         )=-