drivers/misc/ad525x_dpot.c: fix part name typos in defines

There is no runtime effect by this change.  It frees up namespace for
defines erroneously used.  This is required to actually support devices
requiring the namespace, added with "drivers/misc/ad525x_dpot.c: new
features".

All defines touched have the same value defined, after the change.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Chris Verges <chrisv@cyberswitching.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>