Remove unnecessary libpcp.h include from dynamic PMDA

libpcp.h is a private/internal header (marked NOSHIP) that is not
installed. The dynamic PMDA was using it for pmDebugOptions, but this
symbol is already available in the public pmapi.h header which is
already included.

This fixes the compilation error:
  dynamic.c:11:10: fatal error: 'libpcp.h' file not found

Author: tallpsmith

qa/pmdas/dynamic/dynamic.c

@@ -8,7 +8,6 @@
 #include <syslog.h>
 #include <errno.h>
 #include <pcp/pmapi.h>
-#include "libpcp.h"
 #include <pcp/pmda.h>
 #include "domain.h"