Staging: btmtk_usb: Fix indentation for conditional statement

The patch fixes the following checkpatch.pl warning in btmtk_usb.c
WARNING: suspect code indent for conditional statements
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>