arm64: Use FULLKERNEL instead of .ALLSRC in .bin target

[stevek]

Summary

Using .ALLSRC may get additional arguments that we may not want
and could cause the objcopy to fail.

Obtained from: Juniper Networks, Inc.

[emaste]

IMO this is fine, but also ${.ALLSRC} should only ever be ${FULLKERNEL} so not sure how you'd get this case.

[stevek]

In D39639#902347, @emaste wrote:

IMO this is fine, but also ${.ALLSRC} should only ever be ${FULLKERNEL} so not sure how you'd get this case.

In downstream build environments, there could be additional dependencies added.

The ${NM} statement should probably also use ${FULLKERNEL}, since that is what we really want to operate on.

[emaste]

In downstream build environments, there could be additional dependencies added.

Ok, fair enough. It could maybe be something like ${.ALLSRC:[1]} instead but I'm fine with it either way