[PATCH] configure.ac: Update AC_PROG_CC and AC_PROG_LEX for autoconf 2.70

[Mark Wielaard]

On Sat, 2022-10-22 at 21:58 +0200, Mark Wielaard wrote:
> With autoconf 2.70 we must use AC_PROG_CC (which will check for c11
> and c99), for earlier versions we'll use AC_PROG_CC_C99. Also use
> AC_PROG_LEX([noyywrap]), the extra argument is ignored with earlier
> versions, but required for 2.70.

Pushed,

Mark