Documentation: Remove unused "mtdset=" from kernel-parameters.txt

The kernel parameter "mtdset" has been removed two years ago in
commit 61b7f892 ("ARM: s3c: remove all s3c24xx support") and
thus should be removed from the documentation now, too.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240614182508.600113-1-thuth@redhat.com

Documentation/admin-guide/kernel-parameters.txt

@@ -3613,11 +3613,6 @@
 	mtdparts=	[MTD]
 			See drivers/mtd/parsers/cmdlinepart.c
 
-	mtdset=		[ARM]
-			ARM/S3C2412 JIVE boot control
-
-			See arch/arm/mach-s3c/mach-jive.c
-
 	mtouchusb.raw_coordinates=
 			[HW] Make the MicroTouch USB driver use raw coordinates
 			('y', default) or cooked coordinates ('n')