Fixed buildbot failures (compiler warnings, failing tests)

cmd-line-utils/libedit/map.c:
  Fixed compiler warning
cmd-line-utils/libedit/terminal.c:
  Fixed compiler warning
cmd-line-utils/libedit/tty.c:
  Fixed compiler warning
configure.in:
  Fixed that --with-libedit --without-readline works
mysql-test/suite/innodb_plugin/t/innodb_misc1.test:
  Fixed test that failed when characterset was missing