tls: remove redundant assignment to variable decrypted

tls: remove redundant assignment to variable decrypted

The variable decrypted is being assigned a value that is never read,
the control of flow after the assignment is via an return path and
decrypted is not referenced in this path. The assignment is redundant
and can be removed.

Cleans up clang scan warning:
net/tls/tls_sw.c:2150:4: warning: Value stored to 'decrypted' is never
read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20240410144136.289030-1-colin.i.king@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>