Add a few missing uses of types and enums to XML

[kpet]

• OpenCL 1.0 requires cl_char, etc types
• OpenCL 1.2 and cl_khr+_fp64 require cl_double
• cl_khr_fp16 requires CL_HALF_* constants
• cl_khr_icd requires cl_icd_dispatch
• OpenCL 1.0 requires all the CL_M_* constants. The specification does not state which version defines which constant (see #731)

Change-Id: I8eb34ab1eccf727700662ff5f61823d0e8c48ea1

[kpet]

With the change the only missing uses reported by https://github.com/KhronosGroup/OpenCL-Docs/pull/730 are vendor definitions and vendor-reserved enums.