[coreboot] Remaining implicit declaration errors

[Carl-Daniel Hailfinger]

My gcc call unification patch breaks 7 targets because those targets
don't use CFLAGS and thus are not affected by
-Werror-implicit-function-declaration.

In file included from src/mainboard/amd/serengeti_cheetah/apc_auto.c:65:
src/cpu/amd/dualcore/dualcore.c: In function ‘start_other_cores’:
src/cpu/amd/dualcore/dualcore.c:64: error: implicit declaration of
function ‘get_nodes’

In file included from src/mainboard/asus/a8v-e_se/cache_as_ram_auto.c:93:
src/northbridge/amd/amdk8/raminit.c: In function ‘sdram_set_spd_registers’:
src/northbridge/amd/amdk8/raminit.c:2123: error: implicit declaration of
function ‘activate_spd_rom’

In file included from src/mainboard/asus/a8v-e_se/cache_as_ram_auto.c:101:
src/cpu/amd/model_fxx/init_cpus.c: In function ‘init_cpus’:
src/cpu/amd/model_fxx/init_cpus.c:319: error: implicit declaration of
function ‘soft_reset’

In file included from src/mainboard/asus/m2v-mx_se/cache_as_ram_auto.c:98:
src/northbridge/amd/amdk8/raminit_f.c: In function
‘sdram_set_spd_registers’:
src/northbridge/amd/amdk8/raminit_f.c:2848: error: implicit declaration
of function ‘activate_spd_rom’

src/mainboard/digitallogic/msm800sev/cache_as_ram_auto.c: In function
‘cache_as_ram_main’:
src/mainboard/digitallogic/msm800sev/cache_as_ram_auto.c:117: error:
implicit declaration of function ‘done_cache_as_ram_main’

src/mainboard/pcengines/alix1c/cache_as_ram_auto.c: In function
‘cache_as_ram_main’:
src/mainboard/pcengines/alix1c/cache_as_ram_auto.c:209: error: implicit
declaration of function ‘done_cache_as_ram_main’

In file included from src/mainboard/supermicro/h8dme/apc_auto.c:85:
src/cpu/amd/dualcore/dualcore.c: In function ‘start_other_cores’:
src/cpu/amd/dualcore/dualcore.c:64: error: implicit declaration of
function ‘get_nodes’

In file included from src/mainboard/supermicro/h8dmr/apc_auto.c:85:
src/cpu/amd/dualcore/dualcore.c: In function ‘start_other_cores’:
src/cpu/amd/dualcore/dualcore.c:64: error: implicit declaration of
function ‘get_nodes’

Fixes for the above breakage are really appreciated.

Regards,
Carl-Daniel