KVM: PPC: Book3S HV: Fix kmv -> kvm typo

Fix typo in the following kvm function names from:

 kmvhv_counters_tracepoint_regfunc -> kvmhv_counters_tracepoint_regfunc
 kmvhv_counters_tracepoint_unregfunc -> kvmhv_counters_tracepoint_unregfunc

Fixes: e1f288d2 ("KVM: PPC: Book3S HV nestedv2: Add support for reading VPA counters for pseries guests")
Reported-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241114085020.1147912-1-kjain@linux.ibm.com