objtool: Unify STACK_FRAME_NON_STANDARD entry sizes

The C implementation of STACK_FRAME_NON_STANDARD emits 8-byte entries,
whereas the asm version's entries are only 4 bytes.

Make them consistent by converting the asm version to 8-byte entries.

This is much easier than converting the C version to 4-bytes, which
would require awkwardly putting inline asm in a dummy function in order
to pass the 'func' pointer to the asm.

Acked-by: Petr Mladek <pmladek@suse.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>