genirq: Fix kernel-doc markups

Some identifiers have different names between their prototypes
and the kernel-doc markup.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/13a44f4f0c3135e14b16ae8fcce4af1eab27cb5f.1605521731.git.mchehab+huawei@kernel.org