cpuctl.4: Formatting nits

+ Align ioctl list + Pad code examples + Tag spdx license identifier

MFC after:	3 days

share/man/man4/cpuctl.4

@@ -1,3 +1,6 @@
+.\"
+.\" SPDX-License-Identifier: BSD-2-Clause
+.\"
 .\" Copyright (c) 2006-2008 Stanislav Sedov <stas@FreeBSD.org>
 .\" All rights reserved.
 .\"
@@ -63,7 +66,7 @@ All of the supported operations are invoked using the
 .Xr ioctl 2
 system call.
 Currently, the following ioctls are defined:
-.Bl -tag -width CPUCTL_CPUID_COUNT
+.Bl -tag -width indent
 .It Dv CPUCTL_RDMSR Fa cpuctl_msr_args_t *args
 .It Dv CPUCTL_WRMSR Fa cpuctl_msr_args_t *args
 Read/write CPU machine specific register.
@@ -92,6 +95,7 @@ typedef struct {
 	uint32_t	data[4];
 } cpuctl_cpuid_args_t;
 .Ed
+.Pp
 It is equivalent to the
 .Dv CPUCTL_CPUID_COUNT
 request with
@@ -107,6 +111,7 @@ typedef struct {
 	uint32_t	data[4];
 } cpuctl_cpuid_count_args_t;
 .Ed
+.Pp
 The
 .Va level
 field indicates the CPUID level to retrieve,