Staging: iio: ring_sw.c: fix up sparse warnings
Staging: iio: ring_sw.c: fix up sparse warnings

NULL usage, static stuff, etc.

Cc: Jonathan Cameron <09f65b71b7655725897b2fd41a09a0cefe2e1ace@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@suse.de>

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