binutils-2.27 gas has bug that results in the following kind of build
error when assembling bb[cs]i.l on big-endian xtensa targets:
ieee754-sf.S:237: Error: invalid symbolic operand
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>