pwm updated to framework in Linux 3.16-rc7

Signed-off-by: Aurelio Colosimo <aurelio@aureliocolosimo.it>
bathos-mcuio.hex: support for new pwm framework and shell

Signed-off-by: Aurelio Colosimo <aurelio@aureliocolosimo.it>
target/linux/ar71xx/config-3.3: compile new pwm implementation

Signed-off-by: Aurelio Colosimo <aurelio@aureliocolosimo.it>