support reproducible builds

In order to support reproducible builds [1], while using bison to generate
source code, add COMPILE_FLAGS --file-prefix-map [2] to remove build path
prefix and source path prefix in the generated header file.

[1] https://reproducible-builds.org/
[2] https://cgit.git.savannah.gnu.org/cgit/bison.git/commit/?id=dd878d18519689c7bbcd72de4c9f9e53085a3cbf

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
2 files changed