libnewt: Fix cross link using autoconf detected AR
If building on 32bit host and creating 64bit libraries, the target
package builds should not invoke the 32bit hosts's ar. Specifically
you will get an error message like:
x86_64-linux-gcc -m64 --sysroot=/opt/qemux86-64/tmp/sysroots/qemux86-64 -g -o test test.o libnewt.a -Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -lslang
libnewt.a: could not read symbols: Archive has no index; run ranlib to add one
collect2: error: ld returned 1 exit status
Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
