KVM: arm64: Fix hyp_trace clock disabling

KVM: arm64: Fix hyp_trace clock disabling

Fix the disable path in hyp_trace_clock_enable(), which fell through to
re-initialize and reschedule the clock after cancelling the work. Return
early instead.

While at it, cleanup hyp_trace_clock::lock which is unused and
hyp_trace_clock::running which is redundant: the trace_remote framework
already serializes calls to the callback enable_tracing.

Fixes: b22888917fa4 ("KVM: arm64: Sync boot clock with the nVHE/pKVM hyp")
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev> (✓ DKIM/linux.dev)
Link: https://patch.msgid.link/20260715105100.3178255-1-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>