Write env->access_type before a load/store operation instead of relying
on the name of the dyngen operation.
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5785 c046a42c-6fe2-441c-8c8c-71466251a162