attr needs libintl headers and libs. Add in the missing dependency and
ensure the linker flag gets passed in multilib builds by replacing the
PN == BPN check with a class-target override instead.
(From OE-Core rev: c19fb913006eb53025e5db1574d973c8d7ceec76)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>