Removes pre-C99 build and header cruft (#700)

* Committing clang-format changes

* Removes pre-C99 build and header cruft

* Assumes ANSI C headers exist
* Assumes stdbool.h, stdint.h, and inttypes.h are present
* Assumes the C++ compiler can handle stdint.h
* Removes all work-arounds for missing functionality, especially stdbool.h

* Formats source

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

tools/test/perform/sio_engine.c

@@ -16,12 +16,10 @@
 
 #include "hdf5.h"
 
-#ifdef H5_STDC_HEADERS
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
-#endif
 
 #ifdef H5_HAVE_UNISTD_H
 #include <sys/types.h>