(fix) Segmentation fault when using a compound type. (#143)

* (fix) Segmentation fault when using a compound type.

In the case when a compounded attribute is written to dataset
followed by writing the data with a data transform function
to the dataset will result in a segmentation fault. It turns out
the data is classified as compounded while it is not. Now, the
state is always reset first to not compounded followed by the
existing check if the variable is compounded.

* (fix) Removed undesired comment lines.

* (fix) Segmentation fault when using a compound type: added test.

* (fix) Added the missing cmpd_transform.c file to MANIFEST.

* (fix) cmpd_dtransform test: autotools and source header.

Added the cmp_dtransform test to the autotools configuration and
updated the HDF Group copyright header.

Co-authored-by: Jan-Willem Blokland <Jan-Willem.Blokland@Shell.com>

MANIFEST

@@ -1096,6 +1096,7 @@
 ./test/cache_tagging.c
 ./test/chunk_info.c
 ./test/cmpd_dset.c
+./test/cmpd_dtransform.c
 ./test/cork.c
 ./test/corrupt_stab_msg.h5
 ./test/cross_read.c