hwrng: fix spelling mistake in header comment

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

include/linux/hw_random.h

@@ -25,7 +25,7 @@
  *			there is always data available.  *OBSOLETE*
  * @data_read:		Read data from the RNG device.
  *			Returns the number of lower random bytes in "data".
- *			Must not be NULL.    *OSOLETE*
+ *			Must not be NULL.    *OBSOLETE*
  * @read:		New API. drivers can fill up to max bytes of data
  *			into the buffer. The buffer is aligned for any type.
  * @priv:		Private data, for use by the RNG driver.