Remove inconsistent spacing for PIN documentation

The command detailed in the PIN section in the man page exhibit a larger
line spacing than all the other commands documented. The reason is that
we have an addition newline between each of the individual subcommands
in this section.
This patch removes this additional newline to achieve a more consistent
appearance.

nitrocli/doc/nitrocli.1

@@ -1,4 +1,4 @@
-.TH NITROCLI 1 2019-01-05
+.TH NITROCLI 1 2019-01-10
 .SH NAME
 nitrocli \- access Nitrokey devices
 .SH SYNOPSIS
@@ -199,19 +199,16 @@ If the retry counter for the user PIN is zero, you can use the
 If the retry counter for the admin PIN is zero, you have to perform a factory
 reset using \fBgpg\fR(1).
 Use the \fBstatus\fR command to check the retry counters.
-
 .TP
 .B nitrocli pin clear
 Clear the PINs cached by the other commands.
-
 .TP
 \fBnitrocli pin set \fItype\fR
 Change a PIN.
 \fItype\fR is the type of the PIN that will be changed:  \fBadmin\fR to change
 the admin PIN or \fBuser\fR to change the user PIN.
 This command only works if the retry counter for the PIN type is at least one.
 (Use the \fBstatus\fR command to check the retry counters.)
-
 .TP
 .B nitrocli pin unblock
 Unblock and reset the user PIN.