mlxbf_gige: remove own module name define and use KBUILD_MODNAME instead

This patch adds use of KBUILD_MODNAME as defined by the build system,
replacing the definition and use of a custom-defined name.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Link: https://lore.kernel.org/r/20220614212602.28061-1-davthompson@nvidia.com


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