build: consistently mkdir -p output for redirect

build: consistently mkdir -p output for redirect

When running the build in a separate build directory, redirecting output
into a file can error out if the directory does not exist yet.  Some
places already had `mkdir -p` calls, but not all.

Make all occurences of this consistently use `@$(MKDIR_P)`.

(Extension of PR #12575 to catch more places.)

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>