This fixes an error in function i7core_check_error

In commit ca9c90ba which converts the
driver to use double buffering, there is a change in the logic.  Before,
if mce_count was zero, it skipped over a couple of statements and
finished out with a call to the *check_mc_ecc_err function.  The current
code checks to see if mce_count is 0 and then exits.

This change reverts the behavior back to the original where if there are
no errors to report, we skip to the end and call the *check_mc_ecc_err
function.

This fix allows the driver to work again on my Nehalem based blades
again.
Signed-off-by: NVernon Mauery <vernux@us.ibm.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>