Bug#783920: atlas: FTBFS on arm64 in Jessie

[Edmund Grimley Evans]

Source: atlas
Version: 3.10.2-7

It failed to build on arm64 in Jessie. The error was:

make[3]: Entering directory '/«PKGBUILDDIR»/build/atlas-base/lib'
mkdir tmp
cd tmp && \
        ar x ../libatlas.a && \
        if test -f ../libptf77blas.a -a -f ../libptcblas.a; then \
                ar x ../libptf77blas.a && \
                ar x ../libptcblas.a; \
        else \
                ar x ../libf77blas.a && \
                ar x ../libcblas.a; \
        fi
ar: ../libf77blas.a: No such file or directory

(It did build, clearly, on 2015-01-29 on arm-linaro-01. What might
have changed since then?)