testsuite failures on x86_64-pc-linux-gnu with /bin/sh -> dash/ash

[Matthias Klose]

I see testsuite failures on a x86_64-pc-linux-gnu system where /bin/sh points to
dash instead of bash. The variable HOSTING_CRT0 is set in default.exp, derived
from configure.host. When using dash, the \1 in configure.host is expanded to
^A, so the dynamic linker name is set to ^A. Still wondering why I don't see
this behaviour on other architectures. As a workaround, explicitely set
SHELL=/bin/bash when running the testsuite.

  Matthias