intel: Drop legacy execbuffer support
Execbuffer2 support was introduced to libdrm in b5096402, 10 years ago, and no driver has used the old execbuf path since. There's no need to support 10-year-old kernels.
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Execbuffer2 support was introduced to libdrm in b5096402, 10 years ago, and no driver has used the old execbuf path since. There's no need to support 10-year-old kernels.