arm64: Add RV and RN fields for ESR_ELx_WFx_ISS

The ISS field exposed by ESR_ELx contain two additional subfields
with FEAT_WFxT:

- RN, the register number containing the timeout
- RV, indicating if the register number is valid

Describe these two fields according to the arch spec.

No functional change.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-3-maz@kernel.org

arch/arm64/include/asm/esr.h

@@ -133,6 +133,8 @@
 #define ESR_ELx_CV		(UL(1) << 24)
 #define ESR_ELx_COND_SHIFT	(20)
 #define ESR_ELx_COND_MASK	(UL(0xF) << ESR_ELx_COND_SHIFT)
+#define ESR_ELx_WFx_ISS_RN	(UL(0x1F) << 5)
+#define ESR_ELx_WFx_ISS_RV	(UL(1) << 2)
 #define ESR_ELx_WFx_ISS_TI	(UL(3) << 0)
 #define ESR_ELx_WFx_ISS_WFxT	(UL(2) << 0)
 #define ESR_ELx_WFx_ISS_WFI	(UL(0) << 0)