target/arm: Implement NOT (prediates) alias

This alias is defined on EOR (prediates).  While the
same operation could be performed with NAND or NOR,
only bother with the official alias.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220527181907.189259-81-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>