Remove check for hardcoded Xwayland path in gdm.

diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
index 7de7b99c..065325f4 100644
--- a/daemon/gdm-local-display-factory.c
+++ b/daemon/gdm-local-display-factory.c
@@ -245,9 +245,9 @@ struct GdmDisplayServerConfiguration {
         const char *session_type;
 } display_server_configuration[] = {
 #ifdef ENABLE_WAYLAND_SUPPORT
-        { "wayland", GDM_KEY_WAYLAND_ENABLE, "/usr/bin/Xwayland", "wayland" },
+        { "wayland", GDM_KEY_WAYLAND_ENABLE, "", "wayland" },
 #endif
-        { "xorg", GDM_KEY_XORG_ENABLE, "/usr/bin/Xorg", "x11" },
+        { "xorg", GDM_KEY_XORG_ENABLE, "", "x11" },
         { NULL, NULL, NULL },
 };
 
@@ -269,9 +269,6 @@ display_server_enabled (GdmLocalDisplayFactory *factory,
                 if (!gdm_settings_direct_get_boolean (key, &enabled) || !enabled)
                         return FALSE;
 
-                if (!g_file_test (binary, G_FILE_TEST_IS_EXECUTABLE))
-                        return FALSE;
-
                 return TRUE;
         }
 
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<tr><td><span title='2020-09-24 09:16:50 +0200'>2020-09-24</span></td><td><a href='/guix/commit/gnu/packages/uml.scm?id=89ba5f9479a001c89872e42bd1ffdc82bf02b5f7'>gnu: plantuml: Update to 1.2020.17.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/uml.scm (plantuml): Update to 1.2020.17.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-09-18 11:18:09 +0200'>2020-09-18</span></td><td><a href='/guix/commit/gnu/packages/uml.scm?id=6182897c98e11676b9a370da297a688c311f4cab'>gnu: plantuml: Update to 1.2020.16.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/uml.scm (plantuml): Update to 1.2020.16.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Michael Rohleder</td></tr>
<tr><td><span title='2020-08-01 09:13:40 +0200'>2020-08-01</span></td><td><a href='/guix/commit/gnu/packages/uml.scm?id=033b43b2684334655e9c778d8a63f4f61561e759'>gnu: plantuml: Update to 1.2020.15.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/uml.scm (plantuml): Update to 1.2020.15.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Michael Rohleder</td></tr>
<tr><td><span title='2020-02-25 13:47:40 +0100'>2020-02-25</span></td><td><a href='/guix/commit/gnu/packages/uml.scm?id=1fc47a9b491bcc6d3a216592f00f71468a2c80f0'>gnu: plantuml: Update to 1.2020.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/uml.scm (plantuml): Update to 1.2020.1.
[arguments]&lt;#:phases&gt;[delete-extra-from-classpath]: Modify.
</span></span></td><td>Jelle Licht</td></tr>
<tr><td><span title='2020-01-19 17:57:08 +0100'>2020-01-19</span></td><td><a href='/guix/commit/gnu/packages/uml.scm?id=b2e213c3e9c58dc9539a29dcb152fe20df767281'>gnu: plantuml: Use HTTPS home page.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/uml.scm (plantuml)[home-page]: Use HTTPS.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>