gallium/dri: add missing PIPE_BIND_DRI_PRIME handling

e9c3dbd046 added PIPE_BIND_DRI_PRIME but it was only set when
importing a prime buffer.

This commit adds handling of this flag in the other codepath = the
one where the prime buffer is allocated by the render GPU.

With this change PIPE_BIND_DRI_PRIME is still only set for the
render GPU - the display GPU will never see this flag; a future
commit will rename it.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14615>

include/GL/internal/dri_interface.h

@@ -1222,6 +1222,7 @@ struct __DRIdri2ExtensionRec {
  */
 #define __DRI_IMAGE_USE_BACKBUFFER      0x0010
 #define __DRI_IMAGE_USE_PROTECTED       0x0020
+#define __DRI_IMAGE_USE_PRIME_BUFFER    0x0040
 
 
 #define __DRI_IMAGE_TRANSFER_READ            0x1

src/gallium/frontends/dri/dri2.c

@@ -1099,6 +1099,8 @@ dri2_create_image_common(__DRIscreen *_screen,
    }
    if (use & __DRI_IMAGE_USE_PROTECTED)
       tex_usage |= PIPE_BIND_PROTECTED;
+   if (use & __DRI_IMAGE_USE_PRIME_BUFFER)
+      tex_usage |= PIPE_BIND_DRI_PRIME;
 
    img = CALLOC_STRUCT(__DRIimageRec);
    if (!img)

src/loader/loader_dri3_helper.c

@@ -1557,7 +1557,8 @@ dri3_alloc_render_buffer(struct loader_dri3_drawable *draw, unsigned int format,
                                          __DRI_IMAGE_USE_SHARE |
                                          __DRI_IMAGE_USE_LINEAR |
                                          __DRI_IMAGE_USE_BACKBUFFER |
-                                         __DRI_IMAGE_USE_SCANOUT,
+                                         __DRI_IMAGE_USE_SCANOUT |
+                                         __DRI_IMAGE_USE_PRIME_BUFFER,
                                          buffer);
 
          pixmap_buffer = buffer->linear_buffer;