KVM: Update halt polling documentation to note that KVM has 4 module params

Update KVM's halt-polling documentation to correclty reflect that KVM has
4 relevant module params, not 3 params.

Co-developed-by: Rajendran Jaishankar <[e-mail]>
Signed-off-by: Rajendran Jaishankar <[e-mail]>
Signed-off-by: Parshuram Sangle <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
[sean: drop unrelated and misleading doc update]
Signed-off-by: Sean Christopherson <[e-mail]>

Documentation/virt/kvm/halt-polling.rst

···
 Module Parameters
 =================
 
-The kvm module has 3 tuneable module parameters to adjust the global max
-polling interval as well as the rate at which the polling interval is grown and
-shrunk. These variables are defined in include/linux/kvm_host.h and as module
-parameters in virt/kvm/kvm_main.c, or arch/powerpc/kvm/book3s_hv.c in the
-powerpc kvm-hv case.
+The kvm module has 4 tunable module parameters to adjust the global max polling
+interval, the initial value (to grow from 0), and the rate at which the polling
+interval is grown and shrunk. These variables are defined in
+include/linux/kvm_host.h and as module parameters in virt/kvm/kvm_main.c, or
+arch/powerpc/kvm/book3s_hv.c in the powerpc kvm-hv case.
 
 +-----------------------+---------------------------+-------------------------+
 |Module Parameter	|   Description		    |	     Default Value    |