x86, mce: Drop the default decoding notifier

The default notifier doesn't make a lot of sense to call in the
correctable errors case. Drop it and emit the mcelog decoding
hint only in the uncorrectable errors case and when no notifier
is registered. Also, limit issuing the "mcelog --ascii" message
in the rare case when we dump unreported CEs before panicking.

While at it, remove unused old x86_mce_decode_callback from the
header.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Nagananda Chumbalkar <Nagananda.Chumbalkar@hp.com>
Cc: Russ Anderson <rja@sgi.com>
Link: http://lkml.kernel.org/r/20110420102349.GB1361@aftab


Signed-off-by: Ingo Molnar <mingo@elte.hu>