doc: login-utils/*: Fix some warnings from "mandoc -T lint"

mandoc: ./login-utils/chfn.1:96:2: WARNING: skipping paragraph macro: PP empty

mandoc: ./login-utils/lslogins.1:14:2: WARNING: skipping paragraph macro: PP after SH

mandoc: ./login-utils/newgrp.1:18:2: WARNING: skipping paragraph macro: PP empty

mandoc: ./login-utils/nologin.8:19:2: WARNING: skipping paragraph macro: PP empty

mandoc: ./login-utils/sulogin.8:57:2: WARNING: skipping paragraph macro: PP empty

mandoc: ./login-utils/utmpdump.1:61:2: WARNING: skipping paragraph macro: PP after SS

mandoc: ./login-utils/vipw.8:65:2: WARNING: line scope broken: TP breaks I

####

  There is no change in output from "nroff" or "groff".

Signed-off-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>

login-utils/chfn.1

@@ -93,7 +93,6 @@ r = Office (room), w = Office (work) Phone, h = Home Phone.  For example,
 If CHFN_RESTRICT is undefined, then all finger information is read-only.
 This is the default.
 .RE
-.PP
 .SH EXIT STATUS
 Returns 0 if operation was successful, 1 if operation failed or command syntax was not valid.
 .SH AUTHORS

login-utils/lslogins.1

@@ -11,7 +11,6 @@ lslogins \- display information about known users in the system
 .RB [ \-l " \fIlogins\fR]"
 .RI [ username ]
 .SH DESCRIPTION
-.PP
 Examine the wtmp and btmp logs, /etc/shadow (if necessary) and /etc/passwd
 and output the desired data.
 

login-utils/newgrp.1

@@ -15,7 +15,6 @@ is unchanged, but calculations of access permissions to files are performed
 with respect to the new group ID.
 .LP
 If no group is specified, the GID is changed to the login GID.
-.LP
 .SH FILES
 .I /etc/group
 .br

login-utils/nologin.8

@@ -16,7 +16,6 @@ user instead of the default message.
 The exit status returned by
 .B nologin
 is always 1.
-.PP
 .SH OPTIONS
 \fB\-c\fR, \fB\-\-command\fR \fIcommand\fR
 .br

login-utils/sulogin.8

@@ -54,7 +54,6 @@ to get the password.  If these files are damaged or nonexistent, or when
 root account is locked by '!' or '*' at the begin of the password then
 .B sulogin
 will \fBstart a root shell without asking for a password\fP.
-.PP
 .IP
 Only use the
 .B \-e

login-utils/utmpdump.1

@@ -58,7 +58,6 @@ But be warned,
 .B utmpdump
 was written for debugging purposes only.
 .SS File formats
-.PP
 Only the binary version of the
 .BR utmp (5)
 is standardised.  Textual dumps may become incompatible in future.

login-utils/vipw.8

@@ -62,7 +62,6 @@ If the following environment variable exists, it will be utilized by
 .B vipw
 and
 .BR vigr :
-.I
 .TP
 .B EDITOR
 The editor specified by the string