linux-firmware: Add CLM blob to linux-firmware-bcm4373 package

The Country Local Matrix (CLM) blob brcmfmac4373-sdio.clm_blob was not
included with the files for the linux-firmware-bcm4373 package
but instead packaged with linux-firmware.

Signed-off-by: Rudolf J Streif <rudolf.streif@ibeeto.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 18ba64d4)
Signed-off-by: Steve Sakoman <steve@sakoman.com>