git: make was_alias and done_help non-static

git: make was_alias and done_help non-static

'was_alias' variable does not need to store it's value on each
iteration in the loop; this variable gets assigned the result
of run_argv() every time in the loop before being used.

'done_help' variable does not need to be static variable too if
we move it out the loop.

Signed-off-by: Alexander Kuleshov <redacted>
Helped-by: Eric Sunshine <redacted>
Helped-by: Jeff King <redacted>
Signed-off-by: Junio C Hamano <redacted>