encore defconfigs: move to common kernel config for CM10.1 and 10.2

The CM10.2 config has always been fully functional on CM10.1, but
enabling CONFIG_AUDIT changes the kernel ABI, and we wanted to avoid an
ABI break during the CM10.1 stable releases.  Now that the (in all
probability) last 10.1 release has been made, and we've broken the ABI
anyway by merging a bunch of 3.0-stable releases, just use the CM10.2
config on CM10.1+.

Change-Id: Ice1170a3f58def9bd8074ad956371e4a86a42b7e