doc/netlink: Regenerate netlink .rst files if ynl-gen-rst changes

Add ynl-gen-rst.py to the dependencies for the netlink .rst files in the
doc Makefile so that the docs get regenerated if the ynl-gen-rst.py
script is modified. Use $(Q) to honour V=1 in the rules that run
ynl-gen-rst.py

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20231215093720.18774-10-donald.hunter@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>