avoid shadowing outer funcs in modules.lxc.list_()

************* Module salt.modules.lxc
salt/modules/lxc.py:294: [W0621(redefined-outer-name), list_] Redefining name 'info' from outer scope (line 468)
salt/modules/lxc.py:297: [W0621(redefined-outer-name), list_] Redefining name 'state' from outer scope (line 409
Merge pull request #10399 from hulu/lxc-shadowing

avoid shadowing outer funcs in modules.lxc.list_()
folow pattern for checking POLLIN
DRY socket polling/recv
DRY schedule eval