soc/intel/apollolake: Add CONFIG_SMM_TSEG_SIZE

Add SMM_TSEG_SIZE for Apollo Lake and Gemini Lake, set to same value as
used by other Intel SoCs. This is required since commit c078552e71
("soc/intel: Replace sa_get_tseg_size() with CONFIG_SMM_TSEG_SIZE")
removed the use of sa_get_tseg_size() without verifying that all SoCs
actually set the Kconfig being used to replace it.

TEST=build google/reef and verify CONFIG_SMM_TSEG_SIZE set in .config.

Change-Id: Iaac2eaddc6ef3ccfa299b8b10103d26d08881370
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/91166
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Sean Rhodes <sean@starlabs.systems>
Reviewed-by: Guvendik, Bora <bora.guvendik@intel.com>

src/soc/intel/apollolake/Kconfig

@@ -327,6 +327,10 @@ config SMM_RESERVED_SIZE
 	hex
 	default 0x100000
 
+config SMM_TSEG_SIZE
+	hex
+	default 0x800000
+
 config CHIPSET_DEVICETREE
 	string
 	default "soc/intel/apollolake/chipset_glk.cb" if SOC_INTEL_GEMINILAKE