Hexagon (target/hexagon) fix bug in fLSBNEW*

Change fLSBNEW/fLSBNEW0/fLSBNEW1 from copy to "x & 1"
Remove gen_logical_not function
Clean up fLSBNEWNOT to use andi-1 followed by xori-1

Test cases added to tests/tcg/hexagon/misc.c

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1622589584-22571-2-git-send-email-tsimpson@quicinc.com>