Make MPFR build under Cygwin.

/trunk/scripts/build/mpfr.sh | 24 20 4 0 ++++++++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)

# Compute powerpc-specific values

. "${CT_LIB_DIR}/scripts/build/arch/powerpc-powerpc64.sh-common"