mesa: move struct gl_pixelstore_attrib into glthread.h

it will be used there

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27490>

src/mesa/main/glthread.h

@@ -67,6 +67,27 @@ struct gl_context;
 struct gl_buffer_object;
 struct _glapi_table;
 
+/**
+ * Client pixel packing/unpacking attributes
+ */
+struct gl_pixelstore_attrib
+{
+   GLint Alignment;
+   GLint RowLength;
+   GLint SkipPixels;
+   GLint SkipRows;
+   GLint ImageHeight;
+   GLint SkipImages;
+   GLboolean SwapBytes;
+   GLboolean LsbFirst;
+   GLboolean Invert;        /**< GL_MESA_pack_invert */
+   GLint CompressedBlockWidth;   /**< GL_ARB_compressed_texture_pixel_storage */
+   GLint CompressedBlockHeight;
+   GLint CompressedBlockDepth;
+   GLint CompressedBlockSize;
+   struct gl_buffer_object *BufferObj; /**< GL_ARB_pixel_buffer_object */
+};
+
 /* Used by both glthread and gl_context. */
 union gl_vertex_format_user {
    struct {

src/mesa/main/mtypes.h

@@ -1477,28 +1477,6 @@ struct gl_buffer_object
 };
 
 
-/**
- * Client pixel packing/unpacking attributes
- */
-struct gl_pixelstore_attrib
-{
-   GLint Alignment;
-   GLint RowLength;
-   GLint SkipPixels;
-   GLint SkipRows;
-   GLint ImageHeight;
-   GLint SkipImages;
-   GLboolean SwapBytes;
-   GLboolean LsbFirst;
-   GLboolean Invert;        /**< GL_MESA_pack_invert */
-   GLint CompressedBlockWidth;   /**< GL_ARB_compressed_texture_pixel_storage */
-   GLint CompressedBlockHeight;
-   GLint CompressedBlockDepth;
-   GLint CompressedBlockSize;
-   struct gl_buffer_object *BufferObj; /**< GL_ARB_pixel_buffer_object */
-};
-
-
 /**
  * Enum for defining the mapping for the position/generic0 attribute.
  *