bitbake: data: Handle BASH_FUNC shellshock implication

bitbake: data: Handle BASH_FUNC shellshock implication

The shellshock patches changed the way bash functions are exported.
Unfortunately different distros used slightly different formats,
Fedora went with BASH_FUNC_XXX()=() { echo foo; } and Ubuntu went with
BASH_FUNC_foo%%=() {  echo foo; }.

The former causes errors in dealing with out output from emit_env,
the functions are not exported in either case any more.

This patch handles things so the functions work as expected in either
case.

[YOCTO #6880]

(Bitbake rev: 4d4baf20487271aa83bd9f1a778e4ea9af6f6681)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>