llvmpipe: query winsys support for dmabuf mapping
Cherry pick of !29546 (merged) to staging/24.1
Back porting fix so that it will appear in next bug-fix release of 24.1.x.
Should resolve #11332 (closed), #11321
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Cherry pick of !29546 (merged) to staging/24.1
Back porting fix so that it will appear in next bug-fix release of 24.1.x.
Should resolve #11332 (closed), #11321