x86/hyperv: Make hv_setup_sched_clock inline

Make hv_setup_sched_clock inline so the reference to pv_ops works
correctly with objtool updates to detect noinstr violations.
See https://lore.kernel.org/patchwork/patch/1283635/

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1597022991-24088-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>