KVM: x86: hyperv: use defines when parsing hypercall parameters

Avoid open-coding offsets for hypercall input parameters, we already
have defines for them.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

arch/x86/kvm/hyperv.c

@@ -1341,9 +1341,9 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
 #endif
 
 	code = param & 0xffff;
-	fast = (param >> 16) & 0x1;
-	rep_cnt = (param >> 32) & 0xfff;
-	rep_idx = (param >> 48) & 0xfff;
+	fast = !!(param & HV_HYPERCALL_FAST_BIT);
+	rep_cnt = (param >> HV_HYPERCALL_REP_COMP_OFFSET) & 0xfff;
+	rep_idx = (param >> HV_HYPERCALL_REP_START_OFFSET) & 0xfff;
 
 	trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);