docs: process: submitting-patches: Clarify the Reported-by usage

It's unclear from "Submitting Patches" documentation that Reported-by
is not supposed to be used against new features. (It's more clear
in the section 5.4 "Patch formatting and changelogs" of the "A guide
to the Kernel Development Process", where it suggests that change
should fix something existing in the kernel. Clarify the Reported-by
usage in the "Submitting Patches".
Reported-by: NFlorian Eckert <fe@dev.tdt.de>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220127163258.48482-1-andriy.shevchenko@linux.intel.comSigned-off-by: NJonathan Corbet <corbet@lwn.net>

Documentation/process/submitting-patches.rst

@@ -495,7 +495,8 @@ Using Reported-by:, Tested-by:, Reviewed-by:, Suggested-by: and Fixes:
 The Reported-by tag gives credit to people who find bugs and report them and it
 hopefully inspires them to help us again in the future.  Please note that if
 the bug was reported in private, then ask for permission first before using the
-Reported-by tag.
+Reported-by tag. The tag is intended for bugs; please do not use it to credit
+feature requests.
 
 A Tested-by: tag indicates that the patch has been successfully tested (in
 some environment) by the person named.  This tag informs maintainers that