include: Add target environment enums for OpenCL 1.2 and 2.0
Validator: Validate OpenCL capabilities
Update validate capabilities to handle embedded profiles
Add test for OpenCL capabilities validation
Update messages to mention the OpenCL profile used
Re-format val_capability_test.cpp
Re-formatted the source tree with the command:
$ /usr/bin/clang-format -style=file -i \
$(find include source tools test utils -name '*.cpp' -or -name '*.h')
This required a fix to source/val/decoration.h. It was not including
spirv.h, which broke builds when the #include headers were re-ordered by
clang-format.