pgsql: Show information about flex (version and command path) in meson

Show information about flex (version and command path) in meson output

Like bison, this is useful to know which version and command of flex are
detected by meson.  For example, this was useful for me when using
win_flex.exe on Windows.

Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/ZDT3FbmrjBuBthmR@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/72df1d3f1b9d39373edfa8ceed21a000a3cba66f

Modified Files
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meson.build | 5 +++++
1 file changed, 5 insertions(+)