ACPI: prevent ACPI quirk warning mass spamming in logs

The following patch prevent this warning to be displayed again & again (eg:
nine times on my NForce2 motherboard) and thus improve signal to noise
ratio in logs.

The ATI quirk below probably needs a similar "fix" but I don't have
the hardware to test.

Btw arch/x86_64/kernel/early-quirks.c::nvidia_bugs() would probably need to
be synced (but I don't have an x86_64 NVidia motherboard to boot test it).
Still it shows the usefullity of the recent x86 merge thread.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Thierry Vignaud <tvignaud@mandriva.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>