linux-user/syscall: Remove unused variable from execve

From clang-13:
linux-user/syscall.c:8503:17: error: variable 'total_size' set but not used \
    [-Werror,-Wunused-but-set-variable]

Acked-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
1 file changed