ARM: SAMSUNG: Add check for NULL in clock interface
ARM: SAMSUNG: Add check for NULL in clock interface

The clock instance parameter in Samsung clock interface is not being checked
for NULL pointers. Add checks for NULL pointers.

Signed-off-by: Chander Kashyap <740bb265fb814b2df0ab18b75b97f518ea7e7772@linaro.org>
Acked-by: Thomas Abraham <f8cb4d3099c555ac2fa0712396a78d2cd666d4bd@linaro.org>
Signed-off-by: Kukjin Kim <3fc711f4e08bc570a586748633ff7c76d0e1e253@samsung.com>

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