package/kmod: fix build with python 3.8

package/kmod: fix build with python 3.8

Add a patch to filter -Wl,--no-undefined as -Wl,-z,undefs was only
added in binutils 2.30, and therefore is not available in some older
toolchains, causing build failures such as:

/home/naourr/work/instance-1/output-1/host/opt/ext-toolchain/bin/../lib/gcc/aarch64_be-linux-gnu/7.3.1/../../../../aarch64_be-linux-gnu/bin/ld: warning: -z undefs ignored.

Fixes:
 - http://autobuild.buildroot.org/results/06a6d865b6b7d8ebd793bde214f4a4c40e0962e1

Signed-off-by: Fabrice Fontaine <[email protected]>
[Thomas: improve commit log]
Signed-off-by: Thomas Petazzoni <[email protected]>