sound: oss: mpu401.c: Cleaning up missing break in a case
Added a missed break in a case statement
This was found using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Takashi Iwai <tiwai@suse.de>