kernel-doc: include line numbers for function prototypes

kernel-doc: include line numbers for function prototypes

This should solve bad error reports like this one:

	./include/linux/iio/iio.h:0: WARNING: Unknown target name: "devm".

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/56eed0ba50cd726236acd12b11b55ce54854c5ea.1599660067.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-12-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>