fix ARMv6 detection for v8.

The linux kernel now reports the processor information
in "model name" and not in "Processor" anymore.
Both should be checked for backwards compatibility.

As described by:
https://code.google.com/p/v8/issues/detail?id=3112#c16

Change-Id: I8828c1a567281e0d7000106338a2033627e8e397
Reviewed-by: Andras Becsi <andras.becsi@digia.com>