arm64: Add ESR_ELx_FSC_ADDRSZ_L() helper

Although we have helpers that encode the level of a given fault
type, the Address Size fault type is missing it.

While we're at it, fix the bracketting for ESR_ELx_FSC_ACCESS_L()
and ESR_ELx_FSC_PERM_L().

Signed-off-by: Marc Zyngier <maz@kernel.org>