sstate: Avoid indirect bison-native dependencies (via SSTATE_EXCLUDEDEPS_SYSROOT)

sstate: Avoid indirect bison-native dependencies (via SSTATE_EXCLUDEDEPS_SYSROOT)

Avoid adding bison-native to the sysroot without a specific
dependency in the recipe. This means indirect dependencies
(e.g. X -> Y -> binutils-cross -> bison-native) no longer meet the
dependency incidentally. This improves determinism and avoids build
failures when people switch to external toolchains.

Based on an idea by Richard Purdie:
    http://lists.openembedded.org/pipermail/openembedded-core/2018-January/146324.html

(From OE-Core rev: b7edc20cc2dd82989bd9561f860cb25478a40f69)

Signed-off-by: André Draszik <andre.draszik@jci.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>