dct_sel_base_off is declared as a u64 but we're only using the lower 32
bits because of a shift wrapping bug. This can possibly truncate the
upper 16 bits of DctSelBaseOffset[47:26], causing us to misdecode the CS
row.

Fixes: c8e518d5 ('amd64_edac: Sanitize f10_get_base_addr_offset')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20160120095451.GB19898@mwandaSigned-off-by: Borislav Petkov <bp@suse.de>