spd/lp4x: Generate initial SPD for H54G68CYRBX248

Generate initial SPD for H54G68CYRBX248

BUG=b:239888704
BRANCH=firmware-brya-14505.B
TEST=util/spd_tools/bin/spd_gen spd/lp4x/memory_parts.json lp4x

Change-Id: Iae75391938446e9ee387b779ddcaa378a23ee52e
Signed-off-by: Wisley Chen <wisley.chen@quanta.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66070
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

spd/lp4x/set-1/parts_spd_manifest.generated.txt

@@ -30,3 +30,4 @@ H54G56CYRBX247,spd-3.hex
 K4U6E3S4AB-MGCL,spd-1.hex
 K4UBE3D4AB-MGCL,spd-3.hex
 MT53E2G32D4NQ-046 WT:C,spd-10.hex
+H54G68CYRBX248,spd-2.hex