EDAC: Remove arbitrary limit on number of channels

Currently set to "6", but the reset of the code will dynamically
allocate as needed.  We need to go to "8" today, but drop the check
completely to save doing this again when we need even larger numbers.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>