doc tools: better handle KBUILD_VERBOSE
As reported by Jacob, there are troubles when KBUILD_VERBOSE is
set at the environment.
Fix it on both kernel-doc and sphinx-build-wrapper.
Reported-by: Jacob Keller <jacob.e.keller@intel.com>
Closes: https://lore.kernel.org/linux-doc/9367d899-53af-4d9c-9320-22fc4dbadca5@intel.com/
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Tested-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <
7a99788db75630fb14828d612c0fd77c45ec1891.
1774591065.git.mchehab+huawei@kernel.org>