x86/platform: Make X86_GOLDFISH depend on X86_EXTENDED_PLATFORM

All non-PC platforms are supposed to be dependent on this
option.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jun Nakajima <jnakajim@gmail.com>
Link: http://lkml.kernel.org/n/tip-Bcihhqhstm67fchjnkxoiJbu@git.kernel.org


Signed-off-by: Ingo Molnar <mingo@kernel.org>