[raster] ST_Clip() on a raster without band crashes the server

[pracine]

SELECT ST_Clip(ST_MakeEmptyRaster(42, 42, 0, 0, 1.0, 1.0, 0, 0, 4269), ST_MakeEnvelope(0, 0, 20, 20, 4269));

crashes the server.

When the ST_Clip() crop parameter is set to TRUE, ST_Clip() could just change the extent of the empty raster.... When it is set to false, it could just return the raster unmodified.

[robe]

This still crashes server even at 2.4

[robe]

In 16503:

Fix crasher in raster when fed an empty raster (note was tempted to change the def of empty raster to include raster with no bands but not sure where else that is used, so just revised the clip check to not try to clip if no bands).
References #3055 for PostGIS 2.5 (trunk),
also minor doc fix references #2925 for PostGIS 2.5 (trunk)

[robe]

In 16504:

Fix crasher in raster when fed an empty raster (note was tempted to change the def of empty raster to include raster with no bands but not sure where else that is used, so just revised the clip check to not try to clip if no bands).
References #3055 for PostGIS 2.4.4,
also minor doc fix references #2925 for PostGIS 2.4.4

[robe]

In 16505:

Fix crasher in raster when fed an empty raster (note was tempted to change the def of empty raster to include raster with no bands but not sure where else that is used, so just revised the clip check to not try to clip if no bands).
References #3055 for PostGIS 2.3.7,
also minor doc fix references #2925 for PostGIS 2.3.7
reorder NEWS tickets numerically

[robe]

In 16506:

Fix crasher in raster when fed an empty raster (note was tempted to change the def of empty raster to include raster with no bands but not sure where else that is used, so just revised the clip check to not try to clip if no bands).
Closes #3055 for PostGIS 2.2.7
reorder NEWS tickets numerically