[ARM] 3780/1: Fix iop321 cpuid

Patch from Dan Williams

commit a6a38a66

 changed the iop321 id to a value that does not work with all platforms.  Change the mask to permit bit 11.  Tested on an iq80321 600Mhz CRB.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>