ASoC: bcm2835-i2s: remove unneeded semicolon

A semicolon is not needed after a switch statement.

Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20201101160037.2295512-1-trix@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>