arm64: KVM: Turn system register numbers to an enum

Having the system register numbers as #defines has been a pain
since day one, as the ordering is pretty fragile, and moving
things around leads to renumbering and epic conflict resolutions.

Now that we're mostly acessing the sysreg file in C, an enum is
a much better type to use, and we can clean things up a bit.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index 1050b2b..fd0fbe9 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -27,7 +27,6 @@
 
 #define CPU_GP_REG_OFFSET(x)	(CPU_GP_REGS + x)
 #define CPU_XREG_OFFSET(x)	CPU_GP_REG_OFFSET(CPU_USER_PT_REGS + 8*x)
-#define CPU_SYSREG_OFFSET(x)	(CPU_SYSREGS + 8*x)
 
 	.text
 	.pushsection	.hyp.text, "ax"
@@ -150,7 +149,7 @@
 	// Skip restoring fpexc32 for AArch64 guests
 	mrs	x1, hcr_el2
 	tbnz	x1, #HCR_RW_SHIFT, 1f
-	ldr	x4, [x2, #CPU_SYSREG_OFFSET(FPEXC32_EL2)]
+	ldr	x4, [x3, #VCPU_FPEXC32_EL2]
 	msr	fpexc32_el2, x4
 1:
 	ldp	x4, lr, [sp], #16