libapparmor build fails if byacc instead of bison is installed

[Christian Boltz]

[21:43:11] <cboltz> as I said, I get a syntax error for grammar.y, which means I can't really test it :-/

byacc: e - line 70 of "/home/cb/apparmor/TMP/libraries/libapparmor/src/grammar.y", syntax error
%defines
^

[21:47:18] <sbeattie> cboltz: FYI, byacc is the berkeley yacc implementation, not bison.
[21:47:37] <sbeattie> which probably doesn't support some of the stuff we use.
[21:47:59] <sbeattie> as in, we should probably just straight up require bison.

-> configure should check that bison is installed, and bail out if it only finds byacc

[Zygmunt Krynicki (zyga)]

This is still the case in git master.