radeonsi: do not pass the return type to buffer_load_const
radeonsi: do not pass the return type to buffer_load_const

Overriding it is not allowed anyway, and actually lead to a crash when polygon
stippling was used with monolithic shaders.

Reviewed-by: Marek Olšák <8c7344a1abdb103e79ecfd488098373070c3c70e@amd.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler