Use ".Sy root" instead of ".Em root" when talking about the root user.

Replace MANDOCPROG with "mandoc" now that MANDOCPROG has been removed.

docs/Makefile.in

@@ -32,7 +32,7 @@ scriptdir = $(top_srcdir)/scripts
 # Tools to use
 SED = @SED@
 IGOR = igor
-MANDOC = @MANDOCPROG@
+MANDOC = mandoc
 MANCOMPRESS = @MANCOMPRESS@
 MANCOMPRESSEXT = @MANCOMPRESSEXT@
 TR = @TRPROG@

docs/sudo.man.in

@@ -767,7 +767,7 @@ policy requires that user-specified timeouts be explicitly enabled.
 Run the
 \fIcommand\fR
 as a user other than the default target user (usually
-\fIroot\fR).
+\fBroot\fR).
 The
 \fIuser\fR
 may be either a user name or a numeric user-ID

docs/sudo.mdoc.in

@@ -716,7 +716,7 @@ policy requires that user-specified timeouts be explicitly enabled.
 Run the
 .Ar command
 as a user other than the default target user (usually
-.Em root ) .
+.Sy root ) .
 The
 .Ar user
 may be either a user name or a numeric user-ID

docs/sudo_plugin_python.man.in

@@ -1884,14 +1884,14 @@ will not load the Python interpreter or the Python libraries.
 .PP
 By default, a Python plugin can only import Python modules which are
 owned by
-\fIroot\fR
+\fBroot\fR
 and are only writable by the owner.
 The reason for this is to prevent a file getting imported accidentally
 which is modifiable by a non-root user.
 As
 \fBsudo\fR
 plugins run as
-\fIroot\fR,
+\fBroot\fR,
 accidentally importing such file would make it possible for any user
 (having write access) to execute any code with administrative rights.
 .PP

docs/sudo_plugin_python.mdoc.in

@@ -1535,14 +1535,14 @@ will not load the Python interpreter or the Python libraries.
 .Pp
 By default, a Python plugin can only import Python modules which are
 owned by
-.Em root
+.Sy root
 and are only writable by the owner.
 The reason for this is to prevent a file getting imported accidentally
 which is modifiable by a non-root user.
 As
 .Nm sudo
 plugins run as
-.Em root ,
+.Sy root ,
 accidentally importing such file would make it possible for any user
 (having write access) to execute any code with administrative rights.
 .Pp

docs/sudoreplay.man.in

@@ -214,7 +214,7 @@ Evaluates to true if the command was run as the specified
 By default,
 \fBsudo\fR
 runs commands as the
-\fIroot\fR
+\fBroot\fR
 user.
 .TP 8n
 todate \fIdate\fR

docs/sudoreplay.mdoc.in

@@ -197,7 +197,7 @@ Evaluates to true if the command was run as the specified
 By default,
 .Nm sudo
 runs commands as the
-.Em root
+.Sy root
 user.
 .It todate Ar date
 Evaluates to true if the command was run on or prior to