ARM: OMAP: Fix warnings in musb_procfs.c:

drivers/usb/musb/musb_procfs.c: In function 'musb_proc_write':
drivers/usb/musb/musb_procfs.c:651: warning: ignoring return
value of 'copy_from_user', declared with attribute
warn_unused_result
drivers/usb/musb/musb_procfs.c:725: warning: ignoring return
value of 'copy_from_user', declared with attribute
warn_unused_result

Signed-off-by: Dirk Behme <dirk.behme_at_gmail.com>