security/intel/cbnt: Remove fixed size requirement

The CBnT provisioning tooling in intel-sec-tools are now cbfs aware
and don't need to have a fixed size at buildtime.

Tested on OCP/Deltalake with CBnT enabled.

Change-Id: I446b5045fe65f51c5fa011895cd56dbd25b6ccc7
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55821
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Christopher Meis <christopher.meis@9elements.com>
Reviewed-by: Christian Walter <christian.walter@9elements.com>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/ocp/deltalake/Kconfig

@@ -58,11 +58,4 @@ config CONSOLE_POST
 	bool
 	default y
 
-config C_ENV_BOOTBLOCK_SIZE
-	hex
-	default 0xc000 if FIXED_BOOTBLOCK_SIZE
-	help
-	  This matches the IBB size used for CBnT. Adjust this to the
-	  used CBnT settings.
-
 endif # BOARD_OCP_DELTALAKE

src/security/intel/cbnt/Kconfig

@@ -7,7 +7,6 @@ config INTEL_CBNT_SUPPORT
 	#depends on PLATFORM_HAS_DRAM_CLEAR
 	select INTEL_TXT
 	# With CBnT the bootblock is set up as a CBnT IBB and needs a fixed size
-	select FIXED_BOOTBLOCK_SIZE
 	select TPM_MEASURED_BOOT_INIT_BOOTBLOCK if TPM_MEASURED_BOOT
 	help
 	  Enables Intel Converged Bootguard and Trusted Execution Technology