pwm: pwm-mxs: use devm_* managed functions
pwm: pwm-mxs: use devm_* managed functions

Use devm_* managed functions to have a clean fail-out.

Signed-off-by: Shawn Guo <912cf7eb7d8018e2943586ae6657d21fd4e38239@linaro.org>
Signed-off-by: Thierry Reding <b75a4d02013b0e68ae2c6bb0dcfd4b7bec282dc9@avionic-design.de>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas