perf tools: Factorize high level dso helpers

Factorize multiple definitions of high level dso helpers into the
symbol source file.

The side effect is a general export of the verbose and eprintf
debugging helpers into a new file dedicated to debugging purposes.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>

tools/perf/util/debug.c

@@ -0,0 +1,22 @@
+/* For general debugging purposes */
+
+#include "../perf.h"
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+int verbose = 0;
+
+int eprintf(const char *fmt, ...)
+{
+	va_list args;
+	int ret = 0;
+
+	if (verbose) {
+		va_start(args, fmt);
+		ret = vfprintf(stderr, fmt, args);
+		va_end(args);
+	}
+
+	return ret;
+}