mfd: Check for twl4030-madc NULL pointer
mfd: Check for twl4030-madc NULL pointer

If the twl4030-madc device wasn't registered, and another device, such
as twl4030-madc-hwmon, calls twl4030_madc_conversion() a NULL pointer is
dereferenced.

Signed-off-by: Kyle Manna <3c25b01657254677d3e1a8fd1f0742c5d489bd39@kylemanna.com>
Signed-off-by: Samuel Ortiz <0ba86cb3f08bbb861958e54bd3438887adb4263c@linux.intel.com>

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