arm64/cpufeature: Add missing id_aa64mmfr4 feature reg update

Add missing id_aa64mmfr4 feature register check and update in
update_cpu_features(). Update the taint status as well.

Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20250329034409.21354-2-yangyicong@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: Yicong Yang

arch/arm64/kernel/cpufeature.c

@@ -1403,6 +1403,8 @@ void update_cpu_features(int cpu,
 				      info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2);
 	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR3_EL1, cpu,
 				      info->reg_id_aa64mmfr3, boot->reg_id_aa64mmfr3);
+	taint |= check_update_ftr_reg(SYS_ID_AA64MMFR4_EL1, cpu,
+				      info->reg_id_aa64mmfr4, boot->reg_id_aa64mmfr4);
 
 	taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu,
 				      info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0);