docs: kdoc_parser: fix parser to support multi-word types

docs: kdoc_parser: fix parser to support multi-word types

The regular expression currently expects a single word for the
type, but it may be something like  "struct foo".

Add support for it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <544c73a9e670b6fef1828bf4f2ba0de7d29d8675.1772469446.git.mchehab+huawei@kernel.org>