vr.4: Canonicalize SYNOPSIS + tag SPDX

While here, remove superflouous Nd quoting.

MFC after:	3 days

share/man/man4/vr.4

@@ -33,22 +33,14 @@
 .Os
 .Sh NAME
 .Nm vr
-.Nd "VIA Technologies Rhine I/II/III Ethernet device driver"
+.Nd VIA Technologies Rhine I/II/III Ethernet device driver
 .Sh SYNOPSIS
-To compile this driver into the kernel,
-place the following lines in your
-kernel configuration file:
-.Bd -ragged -offset indent
-.Cd "device miibus"
-.Cd "device vr"
-.Ed
+.Cd device miibus
+.Cd device vr
 .Pp
-Alternatively, to load the driver as a
-module at boot time, place the following line in
+In
 .Xr loader.conf 5 :
-.Bd -literal -offset indent
-if_vr_load="YES"
-.Ed
+.Cd if_vr_load="YES"
 .Sh DESCRIPTION
 The
 .Nm