renderer: return an int in vrend_renderer_init

This is an internal API.

src/virglrenderer.c

@@ -266,8 +266,7 @@ int virgl_renderer_init(void *cookie, int flags, struct virgl_renderer_callbacks
       use_egl_context = 1;
    }
 
-   vrend_renderer_init(&virgl_cbs);
-   return 0;
+   return vrend_renderer_init(&virgl_cbs);
 }
 
 int virgl_renderer_get_fd_for_texture(uint32_t tex_id, int *fd)

src/vrend_renderer.c

@@ -3483,7 +3483,7 @@ static GLenum tgsitargettogltarget(const enum pipe_texture_target target, int nr
    return PIPE_BUFFER;
 }
 
-void vrend_renderer_init(struct vrend_if_cbs *cbs)
+int vrend_renderer_init(struct vrend_if_cbs *cbs)
 {
    int gl_ver;
    virgl_gl_context gl_context;
@@ -3556,6 +3556,8 @@ void vrend_renderer_init(struct vrend_if_cbs *cbs)
    list_inithead(&vrend_state.active_ctx_list);
    /* create 0 context */
    vrend_renderer_context_create_internal(0, 0, NULL);
+
+   return 0;
 }
 
 void

src/vrend_renderer.h

@@ -98,7 +98,7 @@ struct vrend_if_cbs {
    void (*destroy_gl_context)(virgl_gl_context ctx);
    int (*make_current)(int scanout, virgl_gl_context ctx);
 };
-void vrend_renderer_init(struct vrend_if_cbs *cbs);
+int vrend_renderer_init(struct vrend_if_cbs *cbs);
 
 void vrend_insert_format(struct vrend_format_table *entry, uint32_t bindings);
 void vrend_insert_format_swizzle(int override_format, struct vrend_format_table *entry, uint32_t bindings, uint8_t swizzle[4]);