multipath-tool: fix fetch error

WARNING: multipath-tools-0.5.0+git770e6d0da0-r0 do_fetch: Failed to fetch URL git://git.opensvc.com/multipath-tools/.git;protocol=http

, attempting MIRRORS if available
ERROR: multipath-tools-0.5.0+git770e6d0da0-r0 do_fetch: Fetcher failure: Fetch command failed with exit code 128, output:
fatal: Unable to find remote helper for 'http'

removed "protocol=http"

Signed-off-by: Armin Kuster <akuster808@gmail.com>