Some filename cleanup in functions/_PDCLIB.

diff --git a/functions/_PDCLIB/filemode.c b/functions/_PDCLIB/_PDCLIB_filemode.c
similarity index 100%
rename from functions/_PDCLIB/filemode.c
rename to functions/_PDCLIB/_PDCLIB_filemode.c

diff --git a/functions/_PDCLIB/prepread.c b/functions/_PDCLIB/_PDCLIB_prepread.c
similarity index 100%
rename from functions/_PDCLIB/prepread.c
rename to functions/_PDCLIB/_PDCLIB_prepread.c

diff --git a/functions/_PDCLIB/prepwrite.c b/functions/_PDCLIB/_PDCLIB_prepwrite.c
similarity index 100%
rename from functions/_PDCLIB/prepwrite.c
rename to functions/_PDCLIB/_PDCLIB_prepwrite.c

diff --git a/functions/_PDCLIB/print.c b/functions/_PDCLIB/_PDCLIB_print.c
similarity index 100%
rename from functions/_PDCLIB/print.c
rename to functions/_PDCLIB/_PDCLIB_print.c

diff --git a/functions/_PDCLIB/scan.c b/functions/_PDCLIB/_PDCLIB_scan.c
similarity index 100%
rename from functions/_PDCLIB/scan.c
rename to functions/_PDCLIB/_PDCLIB_scan.c