st/glsl_to_tgsi: fix block copies of arrays of doubles

Set the type of the left-hand side to the same as the right-hand side,
so that when the base type is double, the writemask of the MOV instruction
is properly fixed up.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Cc: 13.0 <mesa-stable@lists.freedesktop.org>
1 file changed