soc/amd/common/block/cpu/update_microcode: use raw MSR data

Since mst_t is a union of the struct containing the lower and higher 32
bits and the raw 64 bit value, the address of the microcode update can
be directly written to the raw value instead of needing to split it into
the lower and higher 32 bits and assigning those separately.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I51c84164e81477040a4b7810552d3d65c0e3656b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/73636
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>

src/soc/amd/common/block/cpu/update_microcode.c

@@ -37,8 +37,7 @@ static void apply_microcode_patch(const struct microcode *m)
 	uint32_t new_patch_id;
 	msr_t msr;
 
-	msr.hi = (uint64_t)(uintptr_t)m >> 32;
-	msr.lo = (uintptr_t)m & 0xffffffff;
+	msr.raw = (uintptr_t)m;
 
 	wrmsr(MSR_PATCH_LOADER, msr);