pan/bi: Implement f2f16_rtz
Used in OpenCL (and Vulkan, if I'm not mistaken). Just like f2f16 but with the
rounding mode overriden. Easy enough for us :-)
Fixes test_half.vstore_half_rtz.
Used in OpenCL (and Vulkan, if I'm not mistaken). Just like f2f16 but with the
rounding mode overriden. Easy enough for us :-)
Fixes test_half.vstore_half_rtz.