Remove accidental declaration of buffer block in multi_draw_indirect

[gnl21]

Giving an instance name to a buffer_reference declaration also declares a block with that type, which does not seem to have been the intention. The block is never given a binding (which should not be valid, but see KhronosGroup/glslang#4128) and is never used in the shader, so remove the declaration. There should be no functional change to the sample (verified on Broadcom's implementation).

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[asuessenbach]

The copyright message should look like this now:
Copyright (c) 2021-2025 Holochip Corporation

Besides that: looks good.

[gnl21]

The copyright message should look like this ...

Done, thanks.

[gpx1000]

LGTM; thanks for fixing this.