Onion VFD (#1953)

* Onion VFD feature

* Fixes onion VFD errors with non-sec2 backing store VFDs

* Disables the onion VFD tests w/ ph5diff

* Disables non-sec2 VFDs as onion VFD backing stores

* Committing clang-format changes

* Formatted source

* Typo

* Adds onion VFD tools tests to CMake

* Fixes for v16 API compatibility

* Memset structs to avoid bad frees on errors

* H5Dwrite() calls now use H5T_NATIVE_INT as the memory type vs LE

* Properly decodes checksums on BE machines

* Be more careful about uint64_t to haddr_t/hsize_t conversions

* Another fix for BE data comparison

* Removed double underscores from onion constants

* Replace hard-coded onion header string w/ constant

* Fixes cleanup paths in H5FD__onion_ingest_history()

* Fixed use of size_t revision numbers

* Fix h5dump revision count format string

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

tools/test/h5diff/testfiles/h5diff_900.txt

@@ -0,0 +1,12 @@
+
+file1     file2
+---------------------------------------
+    x      x    /              
+    x      x    /DS1           
+           x    /DS2           
+
+group  : </> and </>
+0 differences found
+dataset: </DS1> and </DS1>
+0 differences found
+EXIT CODE: 1

tools/test/h5diff/testfiles/h5diff_901.txt

@@ -0,0 +1,17 @@
+
+file1     file2
+---------------------------------------
+    x      x    /              
+    x      x    /DS1           
+
+group  : </> and </>
+0 differences found
+dataset: </DS1> and </DS1>
+Not comparable: </DS1> has rank 2, dimensions [4x4], max dimensions [18446744073709551615x18446744073709551615]
+and </DS1> has rank 2, dimensions [8x4], max dimensions [18446744073709551615x18446744073709551615]
+0 differences found
+--------------------------------
+Some objects are not comparable
+--------------------------------
+Use -c for a list of objects without details of differences.
+EXIT CODE: 0

tools/test/h5diff/testfiles/h5diff_902.txt

@@ -0,0 +1,30 @@
+
+file1     file2
+---------------------------------------
+    x      x    /              
+    x      x    /DS1           
+
+group  : </> and </>
+0 differences found
+dataset: </DS1> and </DS1>
+size:           [1x16]           [1x16]
+position        DS1             DS1             difference          
+------------------------------------------------------------
+[ 0 0 ]          0               16              16             
+[ 0 1 ]          1               17              16             
+[ 0 2 ]          2               18              16             
+[ 0 3 ]          3               19              16             
+[ 0 4 ]          4               20              16             
+[ 0 5 ]          5               21              16             
+[ 0 6 ]          6               22              16             
+[ 0 7 ]          7               23              16             
+[ 0 8 ]          8               24              16             
+[ 0 9 ]          9               25              16             
+[ 0 10 ]          10              26              16             
+[ 0 11 ]          11              27              16             
+[ 0 12 ]          12              28              16             
+[ 0 13 ]          13              29              16             
+[ 0 14 ]          14              30              16             
+[ 0 15 ]          15              31              16             
+16 differences found
+EXIT CODE: 1