lang/rust: drop binutils dependency on powerpc

It's not used anymore.

Author: pkubaj

lang/rust/Makefile

@@ -106,8 +106,6 @@ IGNORE=		is only for FreeBSD
 .endif
 
 .if ${ARCH} == powerpc
-# bfd to link rustc_driver; lld currently can't
-BUILD_DEPENDS+=	ld.bfd:devel/binutils
 LIB_DEPENDS+=	libatomic.so:lang/gcc${GCC_DEFAULT}
 MAKE_ENV+=	RUSTFLAGS="-L/usr/local/lib/gcc${GCC_DEFAULT}"
 .else