target/arm: Remove dead code relating to SABA and UABA

target/arm: Remove dead code relating to SABA and UABA

In commit cfdb2c0c95ae9205b0 ("target/arm: Vectorize SABA/UABA") we
replaced the old handling of SABA/UABA with a vectorized implementation
which returns early rather than falling into the loop-ever-elements
code. We forgot to delete the part of the old looping code that
did the accumulate step, and Coverity correctly warns (CID 1428955)
that this code is now dead. Delete it.

Fixes: cfdb2c0c95ae9205b0
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200619171547.29780-1-peter.maydell@linaro.org