tools/flex: Revert "tools/flex: add autoreconf"
This was already done in commit 91e262c6b35a7 ("tools: flex: fix build
with automake 1.15.1")
This reverts commit 6b127d86390f85e92e59f3dba04fa585efb3b2c5.
Signed-off-by: Hauke Mehrtens <[email protected]>
Hauke Mehrtens