soc/amd/*/Kconfig: rework SPL options

soc/amd/*/Kconfig: rework SPL options

Move all security patch level (SPL) related Kconfig options to the
common AMD PSP Kconfig file. Commit 4ab1db82bb30 ("soc/amd: rework SPL
file override and SPL fusing handling") already reworked the SPL
handling, but missed that another Kconfig option
SOC_AMD_COMMON_BLOCK_PSP_FUSE_SPL controlled if the PSP mailbox command
to update the SPL fuses was sent by the code that got added to the build
when PERFORM_SPL_FUSING was selected.

To make things less unexpected, rename PERFORM_SPL_FUSING to
SOC_AMD_COMMON_BLOCK_PSP_SPL since it actually controls if the SPL
support code is added to the build and also rename
SOC_AMD_COMMON_BLOCK_PSP_FUSE_SPL to PERFORM_SPL_FUSING. This changes
what PERFORM_SPL_FUSING will do from including the code that could do
the fusing if another option is set to being the option that controls if
the fusing mailbox command will be set. All SoCs that support SPL now
select SOC_AMD_COMMON_BLOCK_PSP_SPL in their Kconfig, which won't burn
any SPL fuses.

The logic in the Skyrim mainboard Kconfig file is reworked to select
PERFORM_SPL_FUSING for all boards on which the SPL fuses should be
updated; on Guybrush PERFORM_SPL_FUSING default is changed to y for all
variants. The option to include the code that checks the SPL fusing
conditions and allows sending the command to update the SPL fuses if the
corresponding Kconfig is set doesn't need to be added on the mainboard
level, since it's already selected at the SoC level.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I12fd8775db66f16fe632674cd67c6af483e8d4e2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78309
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Matt DeVillier <matt.devillier@amd.corp-partner.google.com>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>