arm: Move gen_set_condexec() and gen_set_pc_im() up in the file

Move the utility routines gen_set_condexec() and gen_set_pc_im()
up in the file, as we will want to use them from a function
placed earlier in the file than their current location.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1491844419-12485-5-git-send-email-peter.maydell@linaro.org