services: base: Deprecate 'agetty-service' procedure.

* doc/guix.texi (Base Services): Replace agetty-service with
agetty-service-type.
* gnu/services/base.scm (agetty-service): Deprecate procedure.
* gnu/system/examples/beaglebone-black.tmpl
(operating-system)[services]: Use agetty-service-type.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

doc/guix.texi

@@ -18160,19 +18160,18 @@ The Mingetty package to use.
 @end table
 @end deftp
 
-@deffn {Scheme Procedure} agetty-service @var{config}
-Return a service to run agetty according to @var{config}, an
-@code{<agetty-configuration>} object, which specifies the tty to run,
-among other things.
-@end deffn
+@defvar agetty-service-type
+Type of the service that runs agetty, which implements virtual and
+serial console log-in.  The value for this service is a
+@code{<agetty-configuration>} object.
+@end defvar
 
 @deftp {Data Type} agetty-configuration
-This is the data type representing the configuration of agetty, which
-implements virtual and serial console log-in.  See the @code{agetty(8)}
-man page for more information.
+Data type representing the configuration of agetty, which specifies the
+tty to run, among other things@footnote{See the @code{agetty(8)}
+man page for more information.}.
 
 @table @asis
-
 @item @code{tty}
 The name of the console this agetty runs on, as a string---e.g.,
 @code{"ttyS0"}.  This argument is optional, it will default to

gnu/services/base.scm

@@ -162,7 +162,7 @@
 
             agetty-configuration
             agetty-configuration?
-            agetty-service
+            agetty-service  ; deprecated
             agetty-service-type
 
             mingetty-configuration
@@ -1210,7 +1210,8 @@ to use as the tty.  This is primarily useful for headless systems."
                  "Provide console login using the @command{agetty}
 program.")))
 
-(define* (agetty-service config)
+(define-deprecated (agetty-service config)
+  agetty-service-type
   "Return a service to run agetty according to @var{config}, which specifies
 the tty to run, among other things."
   (service agetty-service-type config))

gnu/system/examples/beaglebone-black.tmpl

@@ -48,10 +48,10 @@
   (services (append (list (service dhcp-client-service-type)
                           ;; mingetty does not work on serial lines.
                           ;; Use agetty with board-specific serial parameters.
-                          (agetty-service
-                           (agetty-configuration
-                            (extra-options '("-L"))
-                            (baud-rate "115200")
-                            (term "vt100")
-                            (tty "ttyO0"))))
-                  %base-services)))
+                          (service agetty-service-type
+                                   (agetty-configuration
+                                    (extra-options '("-L"))
+                                    (baud-rate "115200")
+                                    (term "vt100")
+                                    (tty "ttyO0"))))
+                    %base-services)))