soc/intel/meteorlake: Implement SoC override to set CPU privilege level

This patch implements SoC overrides to set CPU privilege level for
Meteor Lake SoC.

Change-Id: I33794f51e57dd8e0ffe61dfd2f91c6ef3f9187c9
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70352
Reviewed-by: Ivy Jian <ivy.jian@quanta.corp-partner.google.com>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/meteorlake/cpu.c

@@ -29,6 +29,15 @@ bool cpu_soc_is_in_untrusted_mode(void)
 	return !!(msr.lo & ENABLE_IA_UNTRUSTED);
 }
 
+void cpu_soc_bios_done(void)
+{
+	msr_t msr;
+
+	msr = rdmsr(MSR_BIOS_DONE);
+	msr.lo |= ENABLE_IA_UNTRUSTED;
+	wrmsr(MSR_BIOS_DONE, msr);
+}
+
 uint8_t get_supported_lpm_mask(void)
 {
 	return LPM_S0i2_0 | LPM_S0i2_1 | LPM_S0i2_2;