radeon/vce: adjust the buffer offset when relocation is used
radeon/vce: adjust the buffer offset when relocation is used

We don't plan to use sub-allocated buffers with VCE, but just in case one
slips through, this increases the chances of things working out anyway.

Reviewed-by: Christian König <c7ea837d7a46effe4232b086213468b8b31643bf@amd.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler