MN10300: Differentiate AM33_2 and AM33_3 in config

Differentiate AM33_2 and AM33_3 CPU cores in configuration.  The MN103E010
processor contains an AM33_2 core.

Whilst we're at it, prepare for AM34-based stuff by declaring AM34_2 too.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>