arm64: Fix comment typo

Replace wrong 'FIQ EL1h' comment with 'FIQ EL1t'.

Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Link: https://lore.kernel.org/r/20220721030531.21234-1-Kuan-Ying.Lee@mediatek.com


Signed-off-by: Will Deacon <will@kernel.org>