testlistgeo fails with PROJ 8.0.0

[sebastic]

testlistgeo fails with PROJ 8.0.0:

make[3]: Entering directory '/build/libgeotiff-1.6.0/test'
../test/testlistgeo ../bin/listgeo
============================================
Running ../test/testlistgeo using ../bin/listgeo:
============================================
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
proj_create: unrecognized format / unknown name
diff testlistgeo_out with testlistgeo_out.dist
--- testlistgeo_out     2021-02-21 07:01:34.961336363 +0000
+++ testlistgeo_out.dist.tmp    2021-02-21 07:01:34.957336392 +0000
@@ -1566,6 +1566,9 @@
    ProjFalseEastingGeoKey: 649328.000000 m
    ProjFalseNorthingGeoKey: 665262.000000 m
 GCS: 4258/ETRS89
+Datum: 6258/European Terrestrial Reference System 1989
+Ellipsoid: 7019/GRS 1980 (6378137.00,6356752.31)
+Prime Meridian: 8901/Greenwich (0.000000/  0d 0' 0.00"E)
 Projection Linear Units: 9001/metre (1.000000m)

 Corner Coordinates:
@@ -1616,6 +1619,9 @@
    ProjFalseEastingGeoKey: 649328.000000 m
    ProjFalseNorthingGeoKey: 665262.000000 m
 GCS: 4258/ETRS89
+Datum: 6258/European Terrestrial Reference System 1989
+Ellipsoid: 7019/GRS 1980 (6378137.00,6356752.31)
+Prime Meridian: 8901/Greenwich (0.000000/  0d 0' 0.00"E)
 Projection Linear Units: 9001/metre (1.000000m)

 Corner Coordinates:
@@ -1744,6 +1750,9 @@
    ProjFalseEastingGeoKey: 4321000.000000 m
    ProjFalseNorthingGeoKey: 3210000.000000 m
 GCS: 4258/ETRS89
+Datum: 6258/European Terrestrial Reference System 1989
+Ellipsoid: 7019/GRS 1980 (6378137.00,6356752.31)
+Prime Meridian: 8901/Greenwich (0.000000/  0d 0' 0.00"E)
 Projection Linear Units: 9001/metre (1.000000m)

 Corner Coordinates:
@@ -1790,6 +1799,9 @@
    ProjFalseEastingGeoKey: 4321000.000000 m
    ProjFalseNorthingGeoKey: 3210000.000000 m
 GCS: 4258/ETRS89
+Datum: 6258/European Terrestrial Reference System 1989
+Ellipsoid: 7019/GRS 1980 (6378137.00,6356752.31)
+Prime Meridian: 8901/Greenwich (0.000000/  0d 0' 0.00"E)
 Projection Linear Units: 9001/metre (1.000000m)

 Corner Coordinates:

PROBLEMS HAVE OCCURRED
test file testlistgeo_out saved

make[3]: *** [Makefile:540: check-local] Error 100
make[3]: Leaving directory '/build/libgeotiff-1.6.0/test'

CI caught this too:

https://travis-ci.com/github/OSGeo/libgeotiff/jobs/454302672