KVM: arm64: nv: Fix doc header layout for timers

Stephen reports that 'make htmldocs' spits out a warning
("Documentation/virt/kvm/devices/vcpu.rst:147: WARNING: Definition
list ends without a blank line; unexpected unindent.").

Fix it by keeping all the timer attributes on a single line.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Documentation/virt/kvm/devices/vcpu.rst

@@ -142,9 +142,8 @@ the cpu field to the processor id.
 
 :Architectures: ARM64
 
-2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_VTIMER, KVM_ARM_VCPU_TIMER_IRQ_PTIMER,
-                 KVM_ARM_VCPU_TIMER_IRQ_HVTIMER, KVM_ARM_VCPU_TIMER_IRQ_HPTIMER,
---------------------------------------------------------------------------------
+2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_{VTIMER,PTIMER,HVTIMER,HPTIMER}
+-----------------------------------------------------------------------
 
 :Parameters: in kvm_device_attr.addr the address for the timer interrupt is a
 	     pointer to an int