python3: upgrade 3.9.5 -> 3.9.6

0001-Makefile-fix-Issue36464-parallel-build-race-problem.patch
removed since it is included in 3.9.6

Signed-off-by: Zheng Ruoqin <zhengrq.fnst@fujitsu.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>