builtin/remote.c: teach `-v` to list filters for promisor remotes

builtin/remote.c: teach `-v` to list filters for promisor remotes

`git remote -v` (`--verbose`) lists down the names of remotes along with
their URLs. It would be beneficial for users to also specify the filter
types for promisor remotes. Something like this -

	origin	remote-url (fetch) [blob:none]
	origin	remote-url (push)

Teach `git remote -v` to also specify the filters for promisor remotes.

Closes: https://github.com/gitgitgadget/git/issues/1211
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>