i965/fs: Always provide a default LOD of 0 for TXS and TXL

i965/fs: Always provide a default LOD of 0 for TXS and TXL

We already provide a default LOD for textureQueryLevels and texture() on
non-fragment stages.  However, there are more cases where one is needed
such as textureSize(gsampler2DMS*) in SPIR-V.  Instead of trying to list
out all of the cases one at a time, just provide the default for all TXS
and TXL operations.  This fixes a shader validation error in the new
Sascha deferredmultisampling demo which uses textureSize(gsampler2DMS).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100391
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>
Cc: "13.0 17.0" <mesa-stable@lists.freedesktop.org>