This patch lets all ACPI errors and warnings be printed
even ACPI_DEBUG is disabled.

I removed all "proc entry could not be created" messages
and returned -ENODEV.

I also removed all "Error removing/adding notify handler" messages.
I will provide a second patch (ACPICA) and add a message to 
the add/remove_handler function itself.

This should give the "non kernel debuggers" a chance to figure out
why their xy hardware does not work without the need of recompiling
kernels. And should provide as with better bug reports...

This one is on top of Len's latest 2.6.16-rc1/2 push.

    Thomas