[libdmapsharing] Replace use of deprecated G_CONST_RETURN

[W. Michael Petullo <wmpetullo src gnome org>]

commit 3d79874066e1a1c1bba646135cf5fc5811b0eb55
Author: W. Michael Petullo <mike flyn org>
Date:   Sat Dec 7 20:51:29 2019 -0500

    Replace use of deprecated G_CONST_RETURN
    
    Signed-off-by: W. Michael Petullo <mike flyn org>

 libdmapsharing/dmap-mdns-browser-avahi.c | 2 +-
 libdmapsharing/dmap-mdns-browser-dnssd.c | 2 +-
 libdmapsharing/dmap-mdns-browser.h       | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/libdmapsharing/dmap-mdns-browser-avahi.c b/libdmapsharing/dmap-mdns-browser-avahi.c
index 9a4bec8..808d052 100644
--- a/libdmapsharing/dmap-mdns-browser-avahi.c
+++ b/libdmapsharing/dmap-mdns-browser-avahi.c
@@ -285,7 +285,7 @@ dmap_mdns_browser_stop (DmapMdnsBrowser * browser, GError ** error)
        return TRUE;
 }
 
-G_CONST_RETURN GSList *
+const GSList *
 dmap_mdns_browser_get_services (DmapMdnsBrowser * browser)
 {
        g_return_val_if_fail (browser != NULL, NULL);
diff --git a/libdmapsharing/dmap-mdns-browser-dnssd.c b/libdmapsharing/dmap-mdns-browser-dnssd.c
index 746aeca..64b818e 100644
--- a/libdmapsharing/dmap-mdns-browser-dnssd.c
+++ b/libdmapsharing/dmap-mdns-browser-dnssd.c
@@ -582,7 +582,7 @@ dmap_mdns_browser_error_quark (void)
        return quark;
 }
 
-G_CONST_RETURN GSList *
+const GSList *
 dmap_mdns_browser_get_services (DmapMdnsBrowser * browser)
 {
        g_assert(NULL != browser);
diff --git a/libdmapsharing/dmap-mdns-browser.h b/libdmapsharing/dmap-mdns-browser.h
index c472431..3b51e76 100644
--- a/libdmapsharing/dmap-mdns-browser.h
+++ b/libdmapsharing/dmap-mdns-browser.h
@@ -141,7 +141,7 @@ gboolean dmap_mdns_browser_stop (DmapMdnsBrowser * browser, GError ** error);
  *
  * Returns: (element-type DmapMdnsService) (transfer none): services available to @browser.
  */
-G_CONST_RETURN GSList *dmap_mdns_browser_get_services (DmapMdnsBrowser *
+const GSList *dmap_mdns_browser_get_services (DmapMdnsBrowser *
                                                       browser);
 DmapMdnsServiceType dmap_mdns_browser_get_service_type (DmapMdnsBrowser
                                                               * browser);