cmake: fix build by reordering the cflags definitions

cmake: fix build by reordering the cflags definitions

I've noticed bunch of build errors being emitted by clang-15/gcc-10:

 netifd.h:83:33: error: unused parameter 'level' [-Werror,-Wunused-parameter]

and it seems, that the order of definitions matters as -Wextra probably
enables previously disabled warnings like -Wno-unused-parameter.

So lets fix it, by reordering the cflags definitions.

Fixes: 463a1207f076 ("netifd: Activate -Wextra compile warnings")
Signed-off-by: Petr Štetiar <[email protected]>