staging: wfx: replace compiletime_assert() by BUILD_BUG_ON_MSG()

It seems that BUILD_BUG_ON_MSG() is a bit more popular.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20220113085524.1110708-25-Jerome.Pouiller@silabs.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>