wsi/display: move set atomic cap out of wsi_display_get_connector

In all other cases, we immediately set atomic cap after acquiring a drm
fd:

- wsi_init
- AcquireXlib
- AcquireDrm

wsi_GetDrmDisplayEXT is the only function left where the atomic cap is
set by wsi_display_get_connector. This commit moves the set atomic cap
into wsi_GetDrmDisplayEXT.

Signed-off-by: Yuxuan Shui <yshui@codeweavers.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39166>

src/vulkan/wsi/wsi_common_display.c

@@ -719,14 +719,6 @@ wsi_display_get_connector(struct wsi_device *wsi_device,
    if (drm_fd < 0)
       return NULL;
 
-   /* We set this flag because this is the common entrypoint before we start
-    * using atomic capabilities -- it's a simple bool setting in the kernel to
-    * make the properties we start querying be available, and re-setting it is
-    * harmless.  Otherwise, we'd need to push it up to all the entrypoints that
-    * a drm FD comes thorugh.
-    */
-   drmSetClientCap(drm_fd, DRM_CLIENT_CAP_ATOMIC, 1);
-
    drmModeConnectorPtr drm_connector =
       drmModeGetConnector(drm_fd, connector_id);
 
@@ -4553,6 +4545,8 @@ wsi_GetDrmDisplayEXT(VkPhysicalDevice physicalDevice,
       return VK_ERROR_UNKNOWN;
    }
 
+   drmSetClientCap(drmFd, DRM_CLIENT_CAP_ATOMIC, 1);
+
    struct wsi_display_connector *connector =
       wsi_display_get_connector(wsi_device, drmFd, connectorId);