crypto: Clean up help text for CRYPTO_XXHASH

Btrfs stopped using this xxHash implementation in commit
fe11ac1 ("btrfs: switch to library APIs for checksums").

Signed-off-by: Geert Uytterhoeven <[email protected]>
Link: https://lore.kernel.org/r/3b632975201074ccaa129f4901a66aff87b19742.1772116160.git.geert+renesas@glider.be
Signed-off-by: Eric Biggers <[email protected]>

Author: geertu

crypto/Kconfig

@@ -1036,8 +1036,6 @@ config CRYPTO_XXHASH
 
 	  Extremely fast, working at speeds close to RAM limits.
 
-	  Used by the btrfs filesystem.
-
 endmenu
 
 menu "CRCs (cyclic redundancy checks)"