fscrypt: drop obsolete recommendation to enable optimized ChaCha20

Since the crypto kconfig options are being fixed to enable optimized
ChaCha20 automatically
(https://lore.kernel.org/r/Z8AY16EIqAYpfmRI@gondor.apana.org.au/), it is
no longer necessary to give a recommendation to enable it.

Link: https://lore.kernel.org/r/20250304205501.13797-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

Author: ebiggers

Documentation/filesystems/fscrypt.rst

@@ -428,11 +428,8 @@ API, but the filenames mode still does.
     - Mandatory:
         - CONFIG_CRYPTO_ADIANTUM
     - Recommended:
-        - arm32: CONFIG_CRYPTO_CHACHA20_NEON
         - arm32: CONFIG_CRYPTO_NHPOLY1305_NEON
-        - arm64: CONFIG_CRYPTO_CHACHA20_NEON
         - arm64: CONFIG_CRYPTO_NHPOLY1305_NEON
-        - x86: CONFIG_CRYPTO_CHACHA20_X86_64
         - x86: CONFIG_CRYPTO_NHPOLY1305_SSE2
         - x86: CONFIG_CRYPTO_NHPOLY1305_AVX2