sparc64: fix sparse warnings in sys_sparc_64.c + unaligned_64.c

sparc64: fix sparse warnings in sys_sparc_64.c + unaligned_64.c

Fix following warnings:
kernel/sys_sparc_64.c:643:17: warning: symbol 'sys_kern_features' was not declared. Should it be static?
kernel/unaligned_64.c:297:17: warning: symbol 'kernel_unaligned_trap' was not declared. Should it be static?
kernel/unaligned_64.c:387:5: warning: symbol 'handle_popc' was not declared. Should it be static?
kernel/unaligned_64.c:428:5: warning: symbol 'handle_ldf_stq' was not declared. Should it be static?
kernel/unaligned_64.c:553:6: warning: symbol 'handle_ld_nf' was not declared. Should it be static?
kernel/unaligned_64.c:579:6: warning: symbol 'handle_lddfmna' was not declared. Should it be static?
kernel/unaligned_64.c:643:6: warning: symbol 'handle_stdfmna' was not declared. Should it be static?

Functions that are only used in kernel/ - add prototypes in kernel.h
Functions used outside kernel/ - add prototype in asm/setup.h
Removed local prototypes

One of the local prototypes had wrong signature (return void - not int).

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>