st/mesa: fix R8 bitmap texture for TGSI paths.
The initial patch only fixed up the NIR path, but forgot the TGSI path needed fixing as well.
Fixes: f9222693 ("st/mesa: Prefer R8 for bitmap textures")
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The initial patch only fixed up the NIR path, but forgot the TGSI path needed fixing as well.
Fixes: f9222693 ("st/mesa: Prefer R8 for bitmap textures")