widl: Fix nested parameterized types C / short name output.

widl: Fix nested parameterized types C / short name output.

We append type->name from each parameter when constructing the c_name
of parameterized type. When the parameter is itself a parameterized type
this field contains C++-like name, with template brackets.

Instead this precomputes the names of parameterized types whenever they
are used as a parameter. In this case the format is the same as the C
name, except that __C is used as a namespace separator, instead of _C,
and that there's no namespace or abi prefix included.

Shorthands need to be applied too, altough they have to match the __C.

Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>