fp16 has quite the limited value range and with bigger integers
nir_round_int_to_float might return Inf where it shouldn't depending on
the rounding mode.
Fixes conversions half_rt[npz]_(u)?(int|long) CL CTS tests.
Cc: mesa-stable
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Reviewed-by: Rob Clark <rob.clark@oss.qualcomm.com>
(cherry picked from commit e1ed7de274)
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40359>