iio: frequency: admv1013: fix NULL pointer dereference on str
In the Linux kernel, the following vulnerability has been resolved:
iio: frequency: admv1013: fix NULL pointer dereference on str
When device_property_read_string() fails, str is left uninitialized
but the code falls through to strcmp(str, ...), dereferencing a garbage
pointer. Replace manual read/strcmp with
device_property_match_property_string() and consolidate the SE mode
enums into a single sequential enum, mapping to hardware register
values via a switch consistent with other bitfields in the driver.
Several cleanup patches have been applied to this driver recently so
this will need a manual backport.