glsl: Add basic ARB_gpu_shader_int64 types

glsl: Add basic ARB_gpu_shader_int64 types

This adds the builtins and the lexer support.

To avoid too many warnings, it adds basic support to the type in a few
other places in mesa, mostly in the trivial places.

It also adds a query to be used later for if a type is an integer 32 or 64.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>