driver core: platform: Fix spelling errors in platform.c

There is a word spelling mistake of 'Unegisters', thus
it should be fixed.
Signed-off-by: NTang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20200520141202.19568-1-tangbin@cmss.chinamobile.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/platform.c

@@ -977,7 +977,7 @@ EXPORT_SYMBOL_GPL(__platform_register_drivers);
  * @drivers: an array of drivers to unregister
  * @count: the number of drivers to unregister
  *
- * Unegisters platform drivers specified by an array. This is typically used
+ * Unregisters platform drivers specified by an array. This is typically used
  * to complement an earlier call to platform_register_drivers(). Drivers are
  * unregistered in the reverse order in which they were registered.
  */